THE  REDUCTION  OF  DOMESTIC 
MOSQUITOS 


THE  REDUCTION  OF 
DOMESTIC  MOSQUITOS 

INSTRUCTIONS  FOR  THE  USE  OF  MUNICIPALITIES, 
TOWN  COUNCILS,  HEALTH  OFFICERS,  SANITARY 
INSPECTORS,  AND  RESIDENTS  IN  WARM  CLIMATES 

By    EDWARD    HALFORD    ROSS 

M.R.C.S.  England,  L.R.C.P.  London 

Liverpool  School  of  Tropical  Medicine 

Late  Health  Officer,  Port  Said  and  Suez  Canal  District 


Author  of 
"The  Prevention  of  Fever  on  the  Suez  Canal" 


WITH   ILLUSTRATIONS 


PHILADELPHIA 

P.   BLAKISTON'S  SON   &  CO. 
1012  WALNUT  STREET 

J911 


PRINTED  BY 

TIAZELL,   WATSON    AND  VINEY,    LD. 

LONDON   AND  AYLESBURY, 

ENGLAND. 


TO 

PRINCE   AUGUSTE   D'ARENBERG 

PRESIDENT  OF  THE  SUEZ  CANAL  COMPANY 

AND   TO 

RONALD  ROSS 

THIS   BOOK   IS  DEDICATED 
BY   THE   AUTHOR 


226187 


CONTENTS 


PAGE 


INTRODUCTION       ......         1 

CHAPTER  I 
THE  IMPORTANCE  OF  DOMESTIC  MOSQUITOS     .       16 


•  CHAPTER  II 
THE  LIFE  AND  HABITS  OF  DOMESTIC  MOSQUITOS      24 


« CHAPTER    III 

THE  FEVER  CENSUS 38 

CHAPTER    IV 

ESTIMATING   THE  COST  OF  MOSQUITO  REDUC- 
TION         48 

-CHAPTER   V 
WAYS  AND  MEANS         .....       55 

CHAPTER    VI 
PRELIMINARIES      .         .         .         .         .         .61 


viii  CONTENTS 

CHAPTER   VII 

\i  PAQ 

.  THE  START  OF  THE  MOSQUITO  CAMPAIGN        .       69 

CHAPTER   VIII 
v  *   PROGRESS      .......       78 


CHAPTER   IX 
MOSQUITO  REDUCTION  .....       88 

CHAPTER    X 
REPORTING  PROGRESS   .         .         .         .         .96 

CHAPTER   XI 
FINANCE       ,         ......     104 

CHAPTER    XII 

RESULTS  110 


LIST  OF  ILLUSTRATIONS 


1.     The  common  domestic  mosquitos  :   Stegomyia  calopus  and 

Culex  fatigans  (after  Ooeldi)      .         .          .          Frontispiece 

PAGING  PAGE 

'2.     Culex  and  Anopheles        .          .          .          .          .          •          .18 
-  3.     Larva  of  Stegomyia  calopus.     Breathing-tube  of  Culex  larva       18 

4.  Eggs,  egg-rafts,  and  pupaB  of  domestic  mosquitos.     The  birth 

of  the  mosquito  from  the  pupa  (after  Reaumur)          .       26 

5.  The  larval  metamorphoses  (after  Blanchard)     ...       26 

6.  Head  of  male  Culex  and  head  of   male  Anopheles   (after 

Newstead) 33 

»'  7.     Plan  of    breeding-places  of  domestic   mosquitos   at  New 

Orleans  (after  Boyce) 51 

;8.     Port   Swettenham   in   the   Federated  Malay  States.     Now 

cleared  of  mosquitos,  and  healthy  (after  Watson)         .       56 

9.     A    house    cistern.     It    is    a    breeding-place    for   domestic 

mosquitos  (after  Boyce) 71 

10.  A  water-butt.     A   breeding-place   for    domestic   mosquitos 

(after  Boyce) 71 

11.  A  borrow-pit  in  which  domestic  mosquitos  breed     .          .       85 

12.  A  sewage-flooded  backyard  breeding  domestic  mosquitos  .       85 

13.  Port  Said  on  the  Suez  Canal,  formerly  very  insanitary ; 

now  cleared  of  mosquitos  and  healthy.     Each  house  in 
the  town  is  visited  by  a  mosquito  brigade  at  the  same 
hour  of  the  same  day  every  week     ....       95 
iz 


x  LIST  OF  ILLUSTRATIONS 

FACING  PAGE 

14.  A  favourite  breeding-place  for  domestic  mosquitos  .          .       96 

15.  A  cesspool  under  a  native  hut  will  produce  many  mosquitos 

and  much  sickness    .          .          .          .          .          .          .99 

16.  Native   child   with   an   enormously   enlarged   spleen   from 

malaria  ........       99 

17.  The  town  of  Ismailia  on  the  Suez  Canal,  formerly  very 

malarious ;  now  cleared  of  mosquitos  and  healthy. 
Each  house  in  the  town  is  visited  by  a  mosquito  brigade 
at  the  same  hour  of  the  same  day  every  week  .  .107 

18.  The  town  of  Klang  in  the  Federated  Malay  States,  now 

free  from  mosquitos  and  healthy  (after  Watson)  .         .111 


The  Reduction  of  Domestic 
Mosquitos 

INTRODUCTION 

THE  object  of  this  book  is  to  bring  to  public  notice 
the  necessity  for  the  reduction  of  domestic  mosquitos 
in  towns  and  villages,  and  to  describe  how  it  is  best 
accomplished.  The  experience  that  has  been  gained 
on  the  Suez  Canal,  where  mosquito  reduction  has 
resulted  in  a  great  amelioration  of  the  public  health, 
is  utilised  as  a  basis. 

The  book  is  written  at  the  suggestion  of  Professor 
Ronald  Ross,  who,  after  his  discovery  that  malaria  is 
transmitted  by  mosquitos,  was  the  first  to  suggest 
municipal  measures  against  those  insects  that  infest 
towns  as  well  as  those  more  rural  species  that  com- 
monly carry  malaria.  In  his  book  "  Mosquito  Bri- 
gades and  How  to  Organise  them,"  published  in  1902, 
he  drew  attention  to  the  importance  of  directing 
operations  against  all  kinds  of  mosquitos,  wherever 
communities  of  human  beings  are  afflicted  by  them  ; 
and  he  proposed  and  advised  the  formation  of  bri- 
gades to  fight  the  domestic  species  as  well  as  the 
malaria-carrying  ones. 
1 


2  INTRODUCTION 

The  towns  of  the  Suez  Canal  have  been  cleared 
of  all  kinds  of  mosquitos.  At  Port  Said,  the 
commonest  species  found  before  work  was  started 
were  Culex  fatigans  and  Stegomyia  calopus.  These 
are  perhaps  the  common  varieties  of  domestic 
mosquitos,  and  it  is  these  which  will  be  specially 
considered  in  this  book.  In  most  towns  and  villages 
in  warm  climates  domestic  mosquitos  abound  ;  but 
when  such  towns  are  not  also  afflicted  with  the 
malaria-conveying  Anophelines,  it  is  often  thought 
not  worth  the  necessary  expenditure  to  institute  a 
municipal  campaign  against  the  others.  The  experi- 
ence gained  at  Port  Said  shows  that  this  is  a  fallacy. 
It  is  most  important,  and  indeed  absolutely  neces- 
sary, to  reduce  and  to  abolish,  if  possible,  the  mos- 
quitos that  breed  in  and  near  houses  in  towns  as  well 
as  the  more  rural  sylvan  species  that  carry  malaria. 

The  following  pages,  therefore,  deal  entirely  with 
the  reduction  of  the  genera  Culex  and  Stegomyia  ; 
but  measures  against  them  will  also  be  efficacious  in 
ridding  the  town  of  Anophelines  which  happen  to  be 
breeding  within  its  precincts.  This  was  found  to  be 
the  case  at  Port  Said — though  the  campaign  there 
was  originally  started  against  the  domestic  species 
only ;  the  presence  of  Anophelines  in  that  town  was 
discovered  afterwards. 

By  the  ancient  historians  domestic  mosquitos 
were  considered  a  great  pest ;  for  mosquito  nets  were 
used  by  the  Romans  and  Ancient  Greeks.  Professor 
Ross,  in  his  book  "The  Prevention  of  Malaria," 
writes  : 


HISTORY  3 

"  Mr.  Robert  Gladstone  and  Mr.  Jones  have 
kindly  called  my  attention  to  several  passages  refer- 
ring to  mosquito  nets,  called  conopeum  by  the  Romans, 
after  the  Greeks  (our  word  canopy).  Herodotus 
first  noted  with  surprise  the  use  of  them  in  Egypt ; 
and  they  are  referred  to  later  in  Varro  ('De  Re 
Rustica'),  Horace  ('Epodes'),  Propertius,  Juvenal, 
and  Paulus  Silentiarius  ('Anthologa  Palatina'). 
Horace  says,  6  And  among  the  military  standards, 
oh,  shame  !  the  sun  sees  a  mosquito  curtain  ' ;  and 
Propertius  calls  these  nets  fceda  (foul  or  disgraceful). 
Evidently,  the  ancients  felt  towards  them  as  do  many 
of  our  own  more  manly  colonists,  who  prefer  annoy- 
ance, and  even  sickness,  to  disgrace.  But  Paulus 
Silentiarius  thought  that  they  were  useful  for  a  post- 
prandial siesta  in  order  to  save  the  slaves  the  trouble 
of  using  a  fly-flapper.  Varro  said  that  women  lately 
confined  spent  a  number  of  days  in  them ;  and 
Juvenal  said  that  they  were  used  to  cover  the  cradles 
of  the  rich  and  noble." 

If  these  writers  could  visit  Egypt  now,  they  would 
still  find  the  mosquito  nets  in  most  towns  ;  though 
at  Ismailia  and  Port  Said  this  "  disgrace "  has  at 
last,  after  all  these  years,  been  removed.  The  fact, 
recognised  by  Juvenal,  that  the  poor  cannot  afford 
mosquito  curtains,  explains  the  greater  incidence  of 
fevers  among  children  living  in  the  poverty-stricken 
quarters  of  tropical  towns. 

It  seems  probable  that  the  Ancient  Greeks,  even 
in  the  time  of  Hippocrates  (about  460  B.C.),  associated 
marshes  with  fevers,  though  the  connection  of  the 


4  INTRODUCTION 

homely  urban  mosquito  with  disease  was  not  realised. 
The  text-book  already  quoted  states  that  Empedocles 
of  Agrigentum  is  said  to  have  drained  a  marsh,  and 
made  Selinus  in  Sicily  healthy  about  550  years  B.C. 
Strabo  (first  century  B.C.)  remarks  that  Alexandria 
was  free  from  marsh  fever  in  his  time  (Alexandria  now 
is  surrounded  by  very  salt  sea- water  marshes  in  which 
malaria-carrying  mosquitos  do  not  breed).  I  have 
mentioned  elsewhere  the  possibility  that  marsh  and 
mosquito-carried  disease  may  have  accounted  partly 
for  the  downfall  of  the  ancient  empires  of  Egypt  and 
Mesopotamia,  caused  by  the  over-irrigation  and  want 
of  drainage  in  those  river-dependent  countries  ;  the 
land  of  the  delta  of  the  Nile  is  now  becoming  water- 
logged, owing  to  deficient  drainage  and  excessive 
irrigation  under  the  present-day  civilisation.  Pro- 
fessor Ross  and  Mr.  Jones  have  already  suggested, 
and  collected  considerable  evidence  to  prove,  that 
malaria  assisted  in  the  decadence  of  Greece.  The 
Cretans,  Greeks,  and  Romans  had  some  wonderful 
agricultural  drainage  arrangements,  remains  of  which 
may  be  still  seen  in  some  places  ;  and  there  is  a  re- 
markable old  masonry  drain  under  the  city  of  Bey- 
rout,  which  must  have  existed  for  centuries.  Ancient 
civilisations  probably  realised  the  danger  of  marshes, 
swamps,  and  even  urban  stagnant  water-collections, 
but  their  remedies  were  never  very  successful,  because 
the  actual  cause  of  the  danger — mosquitos — was  not 
understood,  and  was  not  revealed  until  the  end  of 
the  nineteenth  century. 

According  to  Mr.  P.  V.  Theobald,  the  author  of 


EARLY   WORK  5 

the  exhaustive  monograph  on  mosquitos  which  was 
written  at  the  instance  of  Sir  E.  Ray  Lankester, 
formerly  Director  of  the  British  (Natural  History) 
Museum,  the  earliest  attempts  at  a  classification  of 


these  insects  (which  belong  to  the  Diptera,  and  to  the 
family  Culicidse)  was  made  by  the  naturalist  Linnaeus 
in  1785,  who  described  the  genus  Culex  (which 
contains  the  common  domestic  species),  and  upon 
this  genus,  with  its  type  Culex  pipiens,  the  family 


6  INTRODUCTION 

characters  are  founded.  Fabricius  in  1805  first 
designated  the  "  tiger  "  mosquito,  Stegomyia  fasciata, 
although  Villiers  had  probably  described  the  same 
insect  before  ;  Meigen  called  it  Stegomyia  calopus, 
very  soon  after.  In  1825  Latreille  grouped  mosquitos 
generally  under  the  name  Culicidae,  but  only  three 
genera  were  known,  Anopheles,  Culex,  and  Mdes. 
Subsequently,  Robineau-Desvoidy  and  Arribalzaga 
added  several  new  genera,  but  the  classifications  were 
very  confused,  several  names  being  given  by  different 
observers  to  the  same  species.  Even  the  name  mos- 
quito itself  has  many  synonyms  ;  it  is  derived  from 
the  Spanish,  and  means  a  small  fly.  In  England  these 
insects  are  variously  called  gnats  or  mosquitos,  in 
German,  stechmilchen,  in  French,  moustiques  (mos- 
quito net,  moustiquaire),  in  Italian,  zanzari,  in  Span- 
ish, mosquitos,  in  Hindustani,  muckers  (mosquito  net, 
mucher-jala),  and  in  Arabic,  nemoos  (mosquito  net, 
nemoosieh).  But  in  1901  Mr.  Theobald  began  the 
publication  of  his  well-known  monograph,  and  this 
has  become  the  standard  work  on  the  classification 
of  the  insect.  As  he  himself  explains,  the  reason  for 
the  monograph  was  the  discoveries  of  the  important 
part  played  by  mosquitos  in  certain  diseases.  These 
discoveries  are  now  common  knowledge,  and  need  be 
but  shortly  mentioned  here. 

According  to  Nuttall,  it  was  in  1878  that  Bancroft 
and  Cobbold  first  suggested  that  the  human  blood- 
worm, Filaria  bancrofti,  might  be  carried  by  mos- 
quitos. This  suggestion  was  based  on  the  knowledge 
obtaining  then  that  certain  Nematode  and  Cestode 


LATER   WORK  7 

worms,  parasitic  in  certain  animals,  passed  portions 
of  their  life-cycles  within  the  bodies  of  certain  other 
animals  or  insects,  now  called  intermediate  hosts.  At 
the  same  time  Manson  came  to  the  same  conclu- 


sion when  in  China,  and  he  made  his  now  famous  dis- 
covery that  the  embryos  of  Filaria  bancrofti  de- 
velop in  the  tissues  of  mosquitos  which  had  fed  on 
infected  Chinamen,  and  which  had  been  caught  in 
their  houses.  However,  the  final  transfer  of  the 
nearly  developed  embryo  worm  from  the  mosquito  to 


8  INTRODUCTION 

man  has  never  been  practically  demonstrated,  though 
there  is  strong  presumptive  evidence  in  its  favour. 

Then  followed  the  well-known  discovery  by 
Ronald  Ross,  published  by  him  in  1897-9  :  first,  that 
the  domestic  grey  gnat  conveys  the  malaria  parasite 
of  birds  (Proteosoma  danilewski  of  Labbe)  from  one 
bird  to  another,  and  secondly,  that  the  human 
malaria  parasite  of  Laveran  is  similarly  transmitted 
by  certain  mosquitos  of  the  dapple-wing  type  that 
belong  to  the  sub-family  called  Anopheline. 

As  in  the  case  of  filariasis,  the  possibility  of  the 
transmission  of  malaria  by  mosquitos  had  been 
suggested  by  many  observers  ;  but  this  discovery 
differed  from  that  of  Hanson's,  inasmuch  as  the 
whole  of  the  life-history  of  the  malaria  parasite  in  the 
mosquito  was  clearly  demonstrated  and  proved  by 
actual  experiment.  Its  confirmation  was  soon  forth- 
coming from  Koch,  Daniels,  and  from  Bignami, 
Bastianelli,  Stephens,  Christophers,  and  many  others. 
Practical  transmission  experiments  in  human  beings 
were  performed  by  many  observers,  and  this  discovery 
is  now  absolutely  proved. 

Serious  attention  was  consequently  drawn  to  mos- 
quitos as  dangerous  pests.  Immediately  following 
his  discovery,  Ross,  in  1899,  suggested  to  the  Indian 
Government  the  possibility  of  reducing  mosquitos  in 
a  malarious  district,  basing  his  proposals  on  observa- 
tions and  experiments  conducted  during  the  previous 
years  in  India.  These  experiments  showed  that 
mosquitos  in  a  house  could  be  reduced  by  the  simple 
procedure  of  periodically  emptying  out  the  rain-water 


DISCOVERIES  9 

collected  in  tubs  and  pots  in  the  garden.  On  his 
retirement  from  the  Indian  Service,  the  matter  was 
taken  up  by  the  Liverpool  School  of  Tropical  Medi- 
cine, which  had  just  been  established,  and  expeditions 
to  West  Africa  were  organised.  This  was  the  be- 
ginning of  a  movement  which  has  resulted  in  the 
clearing  of  many  unhealthy  spots  and  districts  in 
warm  climates.  Reduction  of  domestic  mosquitos 
is  a  branch  of  this  movement. 

The  discovery  of  the  transmission  of  malaria  by 
mosquitos  was  rapidly  succeeded  by  that  of  the 
transmission  of  yellow  fever  in  a  similar  manner.  At 
the  end  of  last  century,  Reed,  Carrol,  Lazear,  and 
Agramonte,  working  in  Cuba,  found  that  the  ultra- 
microscopic  virus  of  yellow  fever  is  conveyed  from 
one  human  being  to  another  by  the  domestic  species 
of  mosquito,  Stegomyia  calopus.  This  was  followed 
by  the  work  of  Graham  of  Beyrout,  and  of  Ashburn 
and  Craig  in  the  Philippines,  which  showed  that  the 
similar  virus  of  dengue  fever  is  conveyed  by  the 
domestic  mosquito  that  is  so  common,  Culex  fatigans. 

In  the  meantime,  measures  against  malaria  and 
yellow  fever  had  been  started  in  many  places.  For  a 
full  description  of  these,  "  The  Prevention  of  Malaria  " 
quoted  above,  and  "  Mosquito  or  Man,"  by  Sir  Rubert 
Boyce  (London,  Murray),  should  be  consulted  ;  there 
is  only  space  to  mention  shortly  some  of  these  cam- 
paigns here. 

The  first  suggestion,  that  the  best  way  to  extirpate 
mosquito-borne  disease  is  to  reduce  the  number  of 
breeding-places  of  the  insects,  was  made  in  the  letter 


10  INTRODUCTION 

to  the  Government  of  India  before  mentioned,  dated 
February  16,  1899.  This  suggestion  was  published 
in  The  Indian  Medical  Gazette,  and  in  The  British 
Medical  Journal  for  July  1899  ;  and  a  few  months 
later  Professor  Ross  made  similar  proposals  in  detail 
for  Sierra  Leone.  As  a  result,  a  limited  campaign 
against  Anophelines  was  begun  at  Hong-Kong  in  1900 
by  Young  and  Thomson,  and  the  results  published 
by  them  in  The  British  Medical  Journal,  September  16, 
1901.  So  far  as  it  went,  this  limited  campaign  was 
successful,  and  it  holds  the  honour  of  being  the  first. 
Then  Dr.  Doty  instituted,  early  in  1900,  measures  for 
the  reduction  of  all  mosquitos  in  Staten  Island,  near 
New  York.  But  the  first  extensive  campaign  was 
that  started  at  Havana  in  the  spring  of  1900  against 
all  kinds  of  mosquitos.  Havana  is  a  city  of  250,000 
people,  and  it  remains  famous  for  continuing  one  of 
the  largest  and  most  complete  sanitary  campaigns 
ever  organised ;  yellow  fever  has  been  abolished. 
Two  months  after  Havana,  Professor  Ross  followed 
suit  by  organising  a  campaign  against  both  Anophe- 
lines and  Culecines  in  Sierra  Leone,  Bathurst,  and 
other  towns  of  the  Gold  Goast  that  were  infected  with 
malaria.  Simultaneously,  Sir  William  MacGregor, 
G.C.M.G.,  and  Dr.  Strachan  at  Lagos  tried  the  effects 
of  window-screening  and  the  distribution  of  quinine 
and  the  drainage  of  marshes  against  that  disease. 
These  were  the  earliest  campaigns. 

The  clearing  of  Ismailia  in  1902,  at  Professor 
Ross's  advice,  was  the  next  undertaking.  The  town 
was  racked  with  malaria.  Both  Anophelines  and 


PRACTICAL   RESULTS  11 

Culecines  were  abolished,  with  the  result  that 
malaria  and  all  other  fevers  have  disappeared,  except 
for  an  occasional  case  of  typhoid.  Now  mosquito 
nets  are  not  necessary  at  Ismailia.  Then,  in  1905, 
at  New  Orleans,  measures  against  yellow  fever  were 
adopted,  and  Stegomyia  and  all  domestic  species 
dealt  with  during  an  epidemic  of  that  disease  ;  this 
campaign  has  been  fully  reported  by  Sir  Rubert 
Boyce.  But  before  this,  Colonel  Gorgas  and  Dr.  Mal- 
colm Watson  began  their  famous  sanitary  campaigns 
against  all  species  of  mosquitos  in  the  Panama  Canal 
Zone,  and  at  Klang  and  Port  Swettenham  respec- 
tively; the  former  is  reported  in  The  Times,  by  Sir 
Harry  Johnstone,  April  17,  1909,  and  by  Dr.  Osier 
in  The  Lancet  of  October  26,  1909,  and  the  latter  in 
Dr.  Watson's  book  "  The  Prevention  of  Malaria  in 
the  Federated  Malay  States."  The  city  of  Rio  de 
Janeiro  was  made  healthy  by  freeing  it  from  malaria 
and  yellow  fever — the  annual  sanitary  budget  in- 
creasing from  £40,000  to  £680,000  ;  Santos  in  Brazil 
has  been  dealt  with  similarly  (de  Cruz,  The  Times, 
December  28,  1909).  In  addition  to  these,  successful 
campaigns  have  been  carried  on  against  either  one 
or  both  of  these  diseases  at  the  following  places  : 
British  and  Spanish  Honduras,  in  the  Philippines, 
Jamaica,  Antigua,  Mauritius,  and  in  Southern 
Nigeria.  In  Italy,  Greece,  and  in  Algeria  mosquito 
reduction  is  being  conducted  in  various  places.  Even 
India,  where  the  original  discovery  which  has  led  to 
these  great  sanitary  reforms  was  made,  is  now,  after 
ten  years'  thought,  more  seriously  considering  the 


12  INTRODUCTION 

adoption  of  measures  carried  out  so  successfully  in 
other  countries.  Egypt,  with  the  exception  of  the 
Suez  Canal  Zone,  is  still  backward,  and  the  Khedive's 
Government  continues  to  regard  mosquito  reduction 
as  a  fraudulent  fetish.  That  country  is  under  some 
spell.  Its  tombs,  its  mummies,  its  Pyramids,  its 
"  honourable  dead,"  appear  to  be  more  important  to 
it  than  the  health  of  the  living.  The  Sphinx  con- 
tinues to  gaze  over  Cairo  with  its  death-rate  of  40 
per  1,000. 

But  these  mosquito  campaigns  have  always  been 
instituted  on  account  of  either  malaria  or  yellow 
fever.  There  is,  consequently,  an  impression,  even 
among  medical  men,  that  unless  malaria  or  yellow 
fever  actually  exists  in  a  community  there  is  no  neces- 
sity to  try  to  reduce  mosquitos.  Persons  who  have 
been  for  a  long  time  resident  in  warm  climates  may 
become  immune  to  mosquito  bites,  and  do  not  feel 
them,  and  if  they  themselves  are  seldom  sick  from 
malaria,  or  never  have  yellow- jack,  they  are  inclined 
to  laugh  at  the  suggestion  of  an  anti-mosquito  cam- 
paign. They  say :  "  There  are  no  Anophelines  here, 
nor  is  there  any  yellow  fever.  Why  bother  about  Culex 
or  Stegomyia,  then  ?  These  mosquitos  do  no  harm." 

The  Culecine  or  domestic  mosquito  does  no  harm. 
Dengue  fever  is  carried  by  the  domestic  and  ubiquit- 
ous Culex  fatigans.  Yellow  fever  is  transmitted  by 
Stegomyia  calopus,  the  common  speckled  gnat.  And 
if  these  fevers  do  not  exist  in  the  town  there  is  always 
the  possibility  of  their  introduction  in  these  days  of 
rapid  travel  and  communication.  But  is  it  certain 


MOSQUITOS   A   DOMESTIC   PEST  13 

that  these  diseases  do  not  exist  in  a  mild  form  among 
the  native  children,  and  may  not  break  out  in  an 
epidemic  ?  The  same  applies  to  malaria  as  well  as 
to  yellow  and  dengue  fevers.  Is  it  certain  that  the 
town  is  quite  free  from  such  disease  ? 

In  addition  to  this  danger,  which  is  surely  im- 
portant enough,  the  domestic  mosquitos  are  disgust- 
ing insects  that  pass  their  larval  lives  in  cesspools, 
blocked-up  canal-ends,  water-butts,  and  even  in  the 
seal  water  of  drains  and  such-like  collections  of  filthy 
water  ;  and  the  newly  hatched  flying  insects  feed  on 
the  floating  matter  found  in  such  water.  Then  they 
proceed  to  suck  the  blood  of  the  first  human  being 
they  can  find,  thrusting  their  infected  proboscides 
through  his  skin.  The  existence  of  domestic  mos- 
quitos in  a  town  or  village  should  be  regarded  as  a 
sign  of  insanitation,  and  their  numbers  as  a  measure 
of  that  insanitation. 

Mosquitos  are  a  terrible  pest.  It  is  difficult  for 
people  at  home  to  realise  what  a  worry  they  are. 
While  one  is  working  or  reading  in  the  evening  or 
trying  to  write  in  one's  office  in  the  daytime,  the 
Culex  or  the  Stegomyia  is  biting  one's  ankles  or  wrists. 
Work  must  be  stopped  while  searching  for  a  fly-flapper 
or  a  weapon  of  some  sort.  Then  ensues  a  hunt  in 
which  the  mosquito  generally  has  the  best  of  it. 
Settle  down  to  read  again.  "  Ping  "  behind  the  ear. 
Fly-flapper  again.  Then  the  same  hunt — no  rest,  no 
peace.  It  is  bang,  flap,  scratch,  rub,  itch,  rub  again, 
complaining  incessantly.  All  work  ends.  The  only 
restful  place  is  in  the  mosquito  curtain ;  but  how  hot 


14  INTRODUCTION 

and  unhealthy  it  is !  The  air  inside  does  not  stir. 
If  there  is  any  wind  the  mosquito  net  will  keep  it  out. 
It  is  too  hot  to  tolerate  bed  clothes  inside  this  muslin 
bag.  Then  if  a  hand  or  foot  touches  the  net  during 
sleep,  a  mosquito  will  wreak  her  vengeance  by  thrust- 
ing her  proboscis  through  the  mesh,  and  then  the 
disturbed  sleep  and  the  constant  itching  and  scratch- 
ing. These  things  must  be  endured  to  be  realised. 
Think  of  the  number  of  people  who  cannot  afford 
even  a  mosquito  curtain.  Think  of  the  children. 
How  much  better  to  get  rid  of  mosquitos  entirely, 
and  live  in  comfort ! 

The  reduction  of  the  domestic  species  of  mos- 
quitos presents  no  difficulties.  Given  the  necessary 
means,  it  requires  only  organisation  and  perseverance. 
It  should  be  regarded  as  a  measure  of  economic  im- 
portance, for  it  improves  the  public  health.  In  all 
towns  where  mosquitos  exist  the  local  authority 
should  be  forced  to  undertake  their  reduction  as  a 
routine  measure,  and  it  should  not  be  left  to  private 
enterprise.  The  cost  of  the  mosquito  campaign 
should  be  included  in  the  municipal  budget  as  a  very 
desirable  reform. 

Mosquito  prevention  in  towns  has  certain  definite 
results,  if  properly  carried  out. 

1.  It  prevents  certain  diseases. 

2.  It  is  a  popular  measure. 

3.  It  necessitates  a  regular  weekly  examination 
of  houses,  yards,  latrines,  ashpits,  water-closets,  cess- 
pools,  and    all   insanitary    places    by    the    sanitary 
authority ;    and    if    the    public    believes    that    this 


THE    ECONOMY   OP   REDUCTION  16 

examination  is  being  carried  out  in  order  to  prevent 
mosquitos  there  will  be  no  opposition. 

4.  It  interests  the  inhabitants,  and  encourages 
them  to  notify  sickness  and  the  return  of  mosquitos 
to  the  local  authority. 

The  cost  is  not  great.  It  varies,  of  course,  in 
different  countries,  for  it  is  dependent  upon  several 
variables,  such  as  the  cost  of  labour,  petroleum,  etc. 
But  a  municipal  rate  of  sixpence  per  head  of  popula- 
tion per  year  in  large  towns  will  generally  cover  the 
cost  of  the  upkeep  of  a  mosquito  campaign,  though 
this  rate  may  be  increased  owing  to  a  heavy  summer 
rainfall,  much  exposed  infiltration  water,  irrigated 
gardens  or  parks,  and  decreased  by  a  complete  system 
of  sewerage  with  good  and  constant  pressure  on  the 
town  water-mains,  and  other  factors. 

But  if  a  mosquito  campaign  is  persevered  with  its 
cost  will  gradually  diminish,  as  it  has  done  at  Port 
Said.  Then  the  organisation  may  be  utilised  for 
further  sanitary  work.  It  will  be  a  trained  organisa- 
tion, and  can  be  taught  to  report  on  the  presence  of 
diseases  other  than  those  conveyed  by  mosquitos  ;  it 
can  be  made  to  examine  unhealthy  shops  and  over- 
crow J^d  factories,  for  example.  But  the  original 
idea  must  never  be  lost  sight  of.  If  the  mosquito 
work  is  neglected  for  a  single  week,  the  insects  will 
surely  return,  and  then  the  work  will  fall  into  disre- 
pute. Perseverance  and  constant  attention  and 
supervision  are  necessary  for  success ;  but  these, 
with  the  money  expended,  will  be  amply  repaid  by 
the  improved  health  and  comfort  of  every  one. 


CHAPTER    I 

THE   IMPORTANCE   OF   DOMESTIC   MOSQUITOS 

As  described  in  the  Introduction,  it  was  the  dis- 
covery that  malaria  is  conveyed  by  mosquitos  which 
first  seriously  directed  attention  to  the  different 
varieties  of  that  insect.  For  years,  in  India,  Ross 
had  attempted  to  transmit  intermittent  fever  by 
the  common  grey  gnat  and  by  the  speckled  gnat ; 
but  the  attempts  were  unsuccessful.  Then  came 
the  discovery  that  malaria  is  conveyed  from  one 
human  being  to  another  by  the  dapple-wing  mos- 
quito, or  Anopheline.  This  led  to  the  classification  of 
these  insects.  Mr.  Theobald's  classification  is  decided 
largely  by  the  shape  and  form  of  the  microscopic 
scales  which  cover  the  bodies  and  the  veins  of  the 
wings  of  gnats,  and  also  by  the  anatomy  of  their 
proboscides,  etc.  In  this  way  mosquitos  have  been 
separated  into  a  number  of  subfamilies,  genera, 
and  species.  This  is  the  scientific  classification. 

But  there  is  another  classification  that  is  simpler 
than  this  :  it  is  based  on  the  habits  of  the  different 
species.  The  type  of  mosquito  that  inhabits  houses 
in  towns  or  compactly  built  villages  is  different  from 
the  type  that  lives  in  marshes,  forests,  and  on  the 

16 


THE    HOUSE   GNAT  17 

banks  of  rivers.     The  species  that  lay  their  eggs  on 
the  surface  of  water  contained  in  cesspools,  in  the 
dirty   water  in  tubs,   bottles   in  yards,  in  gutters, 
choked  eaves,  rainpipes,   broken  drains,  in  exposed 
collections  of  sewage,  cisterns,  flower- vases,  or  water- 
pots,  are  different  from  those  that  oviposit  in  shallow 
marshes,  on  the  estuaries  of  rivers,  in  streams  that 
flow  slowly  through  woods,  in  the  water  that  collects 
stagnant  at  the  end  of  irrigation  channels,  or  in  ponds 
in  the  jungle.     In  some  places,  of  course,  both  kinds 
of  mosquito  are  found  together.     For  example,  in 
the  houses  of  villages  on  the  borders  of  swamps,  or 
near  ricefields  or  flooded    meadows,  and  in  towns 
where   there  is   much  irrigation,  many  gardens,   or 
public   parks,   the  species   of  mosquito  found  may 
belong  to  both   the  domestic  and  sylvan  families ; 
but  in  the  larger  towns  and  villages  the  domestic 
species  are  always  the  commoner  even  if  the  others 
exist.     This  is   because  mosquitos   will  not  fly  far 
from  their   breeding-places   unless  there  happens  to 
be  no  food  for  them  near  :  the  marsh-gnat  will  remain 
near  the  marsh,  the  house-gnat  will  not  go  far  from 
the  backyard.      Therefore  it  may  be  said  that  the 
kind  of  mosquito  found  commonly  in  towns  belongs, 
for  the  most  part,  to  the  subfamily  called  Culecine  ; 
the    Culecina    are     subdivided     again    into     many 
genera,  the  commonest  of  which  are  the  Culex  and 
Stegomyia ;    and    these    again    into    many    species. 
It    is   these    which    are    dealt    with    here ;    other 
works   must   be   consulted   if    the   malaria-carrying 
Anopheline  is  very  common  in  the  town.     But  for 
2 


18  THE  IMPORTANCE   OP  DOMESTIC  MOSQUITOS 

the  sake  of  those  who  are  not  familiar  with  the 
different  characters  of  the  insects,  it  may  be  as  well 
to  describe  the  different  appearances.  The  Culex 
stands  on  the  wall  or  mosquito  net  with  its  body 
parallel  to  the  surface  ;  the  Anopheles  holds  its  body 
straight  out  almost  perpendicular  to  the  wall.  The 
Culex  rarely  has  marked  wings  ;  the  Anopheles  nearly 
always  has  spotted  wings.  The  female  Culex  has 
short  palpae ;  the  female  Anopheles  has  long  palpae. 
The  two  insects  have  so  often  been  pictured  to- 
gether, and  their  difference  is  so  well  known,  that 
their  discrimination  is  an  easy  matter.  All  medical 
men  know  the  Anopheline  from  the  Culecine. 

The  Culecine  mosquito  has  many  varieties  or 
species,  but  for  practical  purposes  these  may  be  col- 
lected into  two  groups — the  common  grey  gnat  and 
the  speckled  gnat.  These  two  forms  are  generally 
found  together,  in  warm  climates,  in  towns,  villages, 
standing  camps,  and  on  board  ships — in  fact,  in 
all  communities  of  human  beings.  The  grey 
gnat  is  a  sombre,  grey  or  brown,  or  even  a  black 
mosquito  which  haunts  rooms  in  the  evening  or  at 
night.  In  the  early  morning  it  can  always  be  seen 
resting  on  the  mosquito  curtain  tired  and  well  fed 
after  its  nocturnal  labours.  It  likes  to  have  a  final 
feed  just  before  dawn.  The  speckled  Stegomyia  is 
the  brightly  coloured,  black-and-white  striped  mos- 
quito which  bites  in  the  daytime,  especially  just 
after  the  dawn.  It  haunts  dark  clothes  and  shady 
verandas.  These  are  the  two  common  domestic 
mosquitos. 


Culex. 


Anopheles. 


Anopheles. 


Larva  of  Stegomyia  calopus. 
Inset :  breathing-tube  of  Culex  larva. 


p.  18] 


A   DANGEROUS   PEST  19 

The  former  of  the  two  species  conveys  dengue 
fever  and  the  latter  yellow  fever ;  both,  therefore, 
are  dangerous  pests.  It  may  be  argued  that  there 
is  no  dengue  nor  yellow  fever  in  the  town,  and 
therefore  there  is  no  need,  nor  is  it  justifiable,  to 
spend  public  money  in  preventing  these  mosquitos. 
But  is  it  certain  that  these  two  diseases  do  not  exist 
in  the  locality  ? 

The  doctors  should  be  interrogated.  It  is  prob- 
able that  there  is  fever  prevailing  in  the  summer. 
The  children  may  be  suffering  from  slight  fever  in 
the  hot  weather.  Information  on  this  point  can  be 
obtained  from  the  schools.  It  may  be  called  sun 
fever,  or  influenza.  Perhaps  a  factory  has  been 
closed  in  the  hot  season  because  the  men  are  sick. 
If  inquiries  are  made  it  will  be  found  that  few  towns 
in  warm  climates  can  claim  an  absolutely  clean  bill 
of  health  all  the  year  round.  Port  Said,  five  years 
ago,  before  the  mosquito  campaign  was  started,  was 
said  to  be  free  from  malaria.  But  the  town  was 
admitted  to  be  unhealthy  ;  its  name  was  a  byword. 
And  then,  on  inquiry,  it  was  found  that,  every 
summer,  people — men,  women  and  children,  Euro- 
pean and  native — used  to  contract  fever.  In  reality 
there  was  fever  of  short  duration — four,  five,  ten 
days'  fever,  followed  by  weakness  and  lassitude. 
Children  were  frequently  ill.  A  mother  would  say 
that  the  baby  was  tired  and  fatigue  ;  she  was  obliged 
to  keep  it  in  bed  for  twelve  days  in  a  stuffy  bedroom. 
Then  such  schools  as  existed  in  those  days  were 
frequently  empty  in  the  hot  weather.  The  men  in 


20  THE   IMPORTANCE   OF  DOMESTIC  MOSQUITOS 

an  engineering  workshop  would  suddenly  have  to 
stop  work  ;  the  manager  would  growl,  saying  that  it 
was  no  good  going  on  with  his  men  sick  :  "  I  have 
discharged  one  gang  and  have  engaged  another ; 
but  now  they  are  sick  too." 

This  was  "  culex  fever."  Repeated  attacks  of 
it  rendered  people  pale  and  lifeless.  The  children 
were  stunted,  anaemic,  and  unhealthy-looking.  Men 
were  frequently  out  of  work  for  days  on  this  account, 
and  after  several  attacks  their  employers  dis- 
charged them.  The  men,  being  unemployed,  wan- 
dered about  the  quays  and  annoyed  the  passengers — 
they  were  forced  to  get  a  livelihood  somehow.  This 
was  the  cause  of  Port  Said's  name.  In  these  days 
sick  men  are  no  use  to  any  one  anywhere. 

Then,  what  a  pest  mosquitos  used  to  be  at  Port 
Said  !  Every  one  complained  about  them.  We  were 
annoyed  all  day  as  well  as  all  night.  Even  in  the 
winter  the  Culecines  were  a  nuisance.  Stegomyia 
calopus  hibernates  in  the  cold,  but  Culex  fatigans 
is  very  troublesome.  The  clerks  in  some  of  the 
offices  were  obliged  to  work  under  mosquito  curtains, 
suspending  them  from  the  gas  brackets  over  their 
desks.  Native  workmen  in  laundries  covered  their 
naked  ankles  with  paper  to  keep  off  mosquitos. 
Passengers  in  the  ships  suffered  too.  The  hotels  and 
residential  houses  and  flats  were  rendered  intolerable 
in  the  evenings.  Mosquitos  followed  one  out  on  to 
the  verandas  and  even  in  the  streets.  After  a 
sleepless  night  one  was  pestered  all  day.  The  cause 
of  it  all  lay  in  the  insanitary  condition  of  the  town. 


AT   PORT   SAID   AND   ISMAILIA  21 

The  cesspools  were  old  and  leaky,  and  in  many 
houses  had  burst  into  the  cellars,  and  there  the 
mosquitos  were  breeding  in  myriads. 

New-comers  felt  the  effects  of  mosquitos  most. 
They  were  inexperienced  in  the  use  of  mosquito 
nets.  They  forgot  to  tuck  them  in  under  their  beds. 
They  were  bitten  terribly.  Their  faces  would  some- 
times be  covered  with  the  marks  produced  by  the 
insects.  Children  especially  suffered.  The  old  resi- 
dent was  inclined  to  mock  the  new-comer,  but  he 
was  bitten  too,  although  he  did  not  feel  the  bites 
so  much  ;  he  was  used  to  them.  Only  the  mosquitos 
themselves  were  really  happy. 

Mosquitos  were  abolished,  and  that  was  the  end 
of  the  trouble.  Malaria  had  been  already  abolished 
at  the  neighbouring  town  of  Ismailia,  and  we  followed 
suit  at  Port  Said.  All  kinds  of  mosquitos  were  dealt 
with  as  at  Ismailia,  and  the  town  is  now  free  from 
fever  carried  by  these  insects.  It  has  made  a  great 
difference  to  life  there.  In  the  course  of  the 
mosquito  campaign  several  interesting  facts  were 
brought  to  light.  Malaria  was  found  ;  the  cause  was 
Anopheles  maculipennis  and  Cellia  pharoensis — both 
species  were  found  breeding  in  dirty  water.  The 
most  insanitary  places  were  discovered  and  dealt 
with.  The  presence  of  a  few  Phlebotomus  flies  and 
an  occasional  case  of  three-day  fever,  which  is  con- 
veyed by  them,  were  noted.  These  small  blood- 
sucking flies  breed  in  stone  walls,  their  eggs  and 
larvae  being  found  in  tiny  crannies  in  the  stone. 
The  culex  fever  disappeared  ;  so  did  the  dengue ; 


22     THE  IMPORTANCE  OF  DOMESTIC  MOSQUITOS 

so  did  filariasis  among  the  natives.  The  house-to- 
house  weekly  visit  of  the  mosquito  brigades  is  now 
a  regular  institution,  and  it  has  been  the  means  of 
accomplishing  many  sanitary  reforms  under  difficult 
political  conditions.  But  this  work  could  never  have 
been  successful  if  the  Anophelines  had  been  attacked 
alone.  It  was  the  reduction  of  the  domestic  mosquito 
which  pleased  the  people  and  which  enabled  the 
weekly  examination  of  the  town  and  the  regular 
inspection  of  the  dirty  native  quarter  to  be  under- 
taken. There  are  no  real  sanitary  laws  in  Egypt, 
and  every  man  was  master  in  his  own  house,  and 
could  build  or  repair  or  not  as  he  liked  ;  we  could 
not  force  him  to  do  anything,  or  even  enter  his  house 
or  premises  without  his  permission.  It  was  for  the 
purpose  of  reducing  their  domestic  mosquitos  that 
the  polyglot  people  of  Port  Said  gave  us  their  per- 
mission to  enter  their  houses  ;  but  when  the  men 
did  get  in  to  the  backyards  and  cellars  they  were 
able  to  do  a  great  deal.  As  soon  as  the  house- 
holder saw  that  we  seriously  intended  to  reduce  his 
domestic  mosquitos  he  no  longer  opposed,  he  actually 
assisted. 

It  is  necessary  therefore  to  reduce  the  Culecine 
mosquito  as  well  as  the  Anopheline.  Deal  with  the 
domestic  mosquito  whether  the  Anopheline  is  present 
or  not  in  the  town.  It  is  a  sanitary  measure  which 
it  is  the  duty  of  citizens  to  perform.  It  is  the  prime 
function  of  municipalities  and  town  councils  to 
undertake  sanitary  reforms  and  to  see  that  they 
succeed.  Health  is  more  important  than  a  beautiful 


HEALTH,  AN  IMPORTANT  MATTER     23 

town  ;  it  is  a  greater  lasting  benefit  than  a  statue 
to  a  great  man.  What  is  the  use  of  an  esplanade, 
a  public  garden,  or  a  monument  if  people  are  too 
ill  to  use  or  to  see  them  ? 


CHAPTER    II 

THE    LIFE    AND    HABITS    OF   DOMESTIC   MOSQUITOS 

BEFORE  attempting  to  exterminate  an  animal  or 
an  insect,  something  must  be  known  of  its  habits  and 
ways.  During  the  past  few  years  much  has  been 
learned  concerning  mosquitos  ;  but  there  still  re- 
mains much  that  is  not  known. 

It  is  only  the  female  mosquito  which  sucks  blood. 
This  statement  has  been  called  in  question,  but  in 
all  probability  it  is  correct.  The  male  mosquito 
has  a  proboscis  that  is  hardly  framed  for  the  purpose 
of  piercing  the  skin.  Certain  authorities  have 
claimed  that  they  have  seen  a  male  mosquito  of  one 
or  two  species  sucking  blood  like  the  female  insect ; 
but  if  such  a  thing  does  occur,  it  must  be  very  rare. 
Of  the  great  number  of  mosquitos  examined  and 
dissected  by  the  author,  on  no  occasion  was  a  male 
found  that  had  blood  in  its  stomach.  The  mosquito 
differs  in  this  respect  from  the  flea.  Both  the  male 
and  female  fleas  live  on  blood.  But  with  mosquitos, 
blood  is  not  the  only  food.  Both  sexes  will  thrust 
their  proboscides  into  various  substances ;  and  so 
far  as  the  domestic  species  are  concerned,  the  filthier 
that  substance  is,  the  more  it  is  enjoyed.  But  the 
fecundated  female  seems  to  require  blood  for  the 

24 


FOOD    AND    FERTILITY  25 

maturation   of  her  ova.     Under  natural  conditions 
it   must   be   very   rare   for   virgin   females   to   suck 
blood.     As  soon  as  the  female  mosquito  has  mated 
with  the  male  she  develops  a  sudden  craving  for 
animal  blood.     The  haematophagus  habit  appears  to 
be  dependent  on  the  presence,  in  the  female,  of  the 
spermatozoa  of  the  male.     This  statement  also  has 
been  called  in  question.     But  of  all  the  mosquitos 
dissected,  among  those  actually  caught  in  the  habi- 
tations of  human  beings,  which  contained  blood  in 
their   stomachs,  not   one   was   found    that   did   not 
have    living    spermatozoa    inside    her    spermathecae. 
From  this  it  must  be  inferred  that  virgin  females  do 
not,  commonly,  take  blood  ;    in  captivity,  perhaps, 
if  they  are  starving  the  unfertilised  female  may  be 
induced  to  pierce  the  skin  with  her  proboscis.     It 
is  interesting  to  try  to  conjecture  the  nature  of  the 
changes,  within  the  female,  caused  by  mating  with 
the  male,  which  induces   such   an   alteration  in  her 
dietary.     In  several  small  animals  and  insects — for 
example,   tadpoles  and  caterpillars — food  is  an   im- 
portant  factor   in   the   determination   of   sex.     The 
well-known  case  of  the  honey-bee  may  be  quoted. 
Here  sex  is  determined  by  fertilisation,  the  males 
originating   from   unfecundated    eggs    by    partheno- 
genesis, while  the  fertilised  eggs  produce  the  females. 
Then    the    food    of    the    larva    determines    whether 
these  females  become  barren  workers  or  the  queen 
bees.     In  the  mosquito,  however,  the  sexual  factor 
determines  the  choice  of  the  food — Nature  appears 
to  have  reversed  her  procedure. 


26     LIFE   AND    HABITS    OF   DOMESTIC   MOSQUITOS 

The  female  mosquito  lays  her  eggs  in  broods. 
After  mating  and  after  some  meals  of  blood  the 
female  returns  to  water  to  oviposit.  The  domestic 
mosquito  prefers  dirty  water  on  which  to  lay  her 
eggs.  She  lays  them  either  in  rafts  of  three  hundred 
at  a  time,  or  more  loosely  bound  together  ;  Culex 
fatigans  affects  the  former,  while  Stegomyia  prefers 
the  latter.  Anophelines  lay  their  eggs  singly.  But 
the  water  collection  must  be  sheltered  from  the 
wind,  for  the  operation  of  laying  three  hundred  or 
more  eggs  requires  some  time,  and  mosquitos  cannot 
withstand  a  gust  of  wind — their  wings  and  legs  are 
delicate  structures.  The  egg-raft  of  the  Culex  is 
about  an  eighth  of  an  inch  in  length,  and  can  be 
readily  seen  floating  on  the  surface  of  the  water. 
The  eggs  of  Stegomyia  merely  cling  together,  and, 
although  they  can  be  seen  by  the  naked  eye,  a  mag- 
nifying glass  is  needed  to  distinguish  the  details  of 
their  form.  The  easiest  way  to  find  mosquito  eggs 
in  a  warm  climate  is  to  leave  a  bucket  of  dirty  water 
in  the  kitchen  for  a  night,  when  the  eggs  will  be 
found  floating  either  in  rafts'  or  in  batches  on  the 
water  in  the  morning.  They  can  then  be  gently 
lifted  off  the  water,  and  examined  under  the  micro- 
scope. 

The  domestic  mosquito  likes  to  lay  her  eggs  on 
the  surface  of  dirty  water,  for  she  knows  that  this  will 
supply  plenty  of  food  for  her  children,  the  larvae, 
when  they  have  hatched  from  the  eggs  into  swimming 
"  wrigglers."  This  can  be  demonstrated  by  an  interest- 
ing experiment.  Place  two  buckets  side  by  side  in  a 


Eggs,  egg-rafts,  and  pupae  of  domestic  mosquitos. 
The  birth  of  the  mosquito  from  the  pupa. 

(After  Reaumur.) 


p.  26J 


The  larval  metamorphoses. 

(After  Bfanchard.) 


MATERNAL    INSTINCT    IN    MOSQUITOS         27 

dark,  quiet  corner  of  a  mosquito-infested  house.  Into 
one  put  some  clean,  filtered  water,  and  into  the  other 
put  an  equal  quantity  of  dirty  water  in  which,  say, 
the  cook  has  washed  the  plates.  Leave  the  buckets 
for  three  days,  and  if  the  water  in  them  is 
then  examined,  numbers  of  mosquito  eggs — batches 
and  rafts— will  be  found  floating  on  the  surface  of 
the  dirty  water,  and  few  or  none  on  the  surface  of 
the  clean  water.  The  maternal  instinct  drives  the 
female  mosquito  of  the  domestic  species  to  lay  her 
eggs  where  her  larvae  will  thrive. 

Each  separate  egg  gives  rise  to  one  mosquito  larva 
or  wriggler.  Each  egg-raft  or  batch  produces,  there- 
fore, a  brood  of  swimming  larvae.  These  small 
aquatic  insects  are  well  known  even  in  England 
during  the  summer.  If  after  a  heat-wave  the 
water-butt  in  the  garden  is  examined,  hundreds 
of  these  fish-like  insects  can  usually  be  seen  in  the 
water.  They  are  worth  watching.  Note  how  they 
avoid  the  direct  sunlight,  and  keep  to  the  shady 
edges  of  the  tub.  Here  they  collect,  their  heads 
hanging  downwards,  their  tails  touching  the  surface 
of  the  water.  When  disturbed,  they  wriggle  down 
to  the  bottom  of  the  water.  They  feed  on  such 
minute,  living  or  dead,  animal  or  vegetable  particles 
as  they  can  find. 

The  Culex  larva  differs  slightly  from  the  Stego- 
myia ;  the  former,  when  resting  near  the  surface  of 
the  water,  is  nearly  perpendicular  to  it,  the  latter  is 
at  an  acute  angle  to  the  surface.  The  Culex  larva 
possesses  a  long  tube  in  its  tail  through  which  it 


28     LIFE   AND    HABITS   OF   DOMESTIC   MOSQUITOS 

breathes  the  air,  the  Stegomyia  has  only  a  short  tube. 
The  mosquito  larva  spends  at  least  ten  days  in  the 
water  before  it  emerges  into  the  air  as  a  full-grown 
mosquito.  During  this  time  it  grows  much  larger, 
and  undergoes  four  moults.  For  the  last  twenty -four 
hours  prior  to  its  birth  into  the  world  as  a  flying 
insect,  it  is  found  in  the  comma-like  stage  known  as 
the  pupa  or  nymph.  During  this  stage  it  bobs  about 
in  the  water,  breathing  at  the  surface,  but  takes  no 
food.  All  these  stages  are  known  as  the  larval 
metamorphosis. 

From  the  moment  the  mosquito  egg  is  laid,  the 
living  larva  begins  its  battle  of  life.  Its  life  in  the 
egg  itself  is  very  short  if  there  happen  to  be  any  gold- 
fish in  the  water,  or  a  bird  may  gobble  up  the  whole 
egg-raft.  As  soon  as  the  larva  has  left  the  egg  and 
become  a  swimming  wriggler,  its  first  trouble  may  be 
to  find  food.  Its  mother  has  flown  away  to  annoy 
another  human  being  or  animal,  and  has  left  it  to 
take  care  of  itself,  together  with  its  three  hundred 
brothers  and  sisters.  If  the  mosquito  larva  can  find 
suitable  food,  and  the  water  is  warm,  it  grows 
rapidly,  moulting  its  skin  every  two  or  three  days, 
and  gradually  growing  darker  in  colour,  until  at  the 
end  of  the  tenth  day  it  enters  the  pupa  stage  after 
having  shed  its  skin  for  the  last  time. 

Both  the  larva  and  the  pupa  are  not  fish,  but 
insects.  They  must  breathe  the  air  from  the  atmo- 
sphere. The  larva  has  a  tube  at  the  end  of  its  tail, 
which  it  thrusts  through  the  surface  of  the  water, 
and  so  breathes,  The  pupa  has  short  tubes  on  its 


THE    BIRTH    OF    THE    MOSQUITO  29 

back  through  which  it  obtains  air  in  a  similar  manner. 
After  taking  a  breath  of  air  the  larva  goes  down 
again  to  feed.  On  its  head  are  two  swirling  circu- 
latory organs  which  direct  particles  of  food  towards 
its  mouth  ;  the  pupa  does  not  feed. 

The  pupa  stage  lasts,  in  hot  weather,  for  about 
twenty-four  hours  ;  but  this  period  may  be  pro- 
longed if  the  water  is  cold.  During  this  nymph 
stage,  the  winged  insect  is  gradually  forming  within 
the  pupa  skin,  much  as  the  kernel  of  a  nut  becomes 
loosened  within  its  shell. 

While  the  pupa  is  resting  near  the  surface  of  the 
water,  breathing  through  the  air  tubes  on  its  back, 
the  skin  splits  where  the  latter  meets  the  surface. 
Through  the  split  the  head,  antennae,  and  the  pro- 
boscis of  the  mature  flying  mosquito  slowly  emerge 
above  the  water.  The  two  forelegs  are  thrust  out 
and  rest  on  the  water  on  each  side  of  the  pupa-case, 
making  tiny  dimples  on  the  surface  of  the  fluid. 
These  are  followed  by  the  next  pair  of  legs,  and  then 
the  wings  are  born.  For  half  an  hour  the  partly 
hatched  mosquito  remains  floating  on  the  old  pupa 
case,  from  which  it  is  in  process  of  being  born.  The 
wings  are  gently  separated  and  carefully  tried,  and 
ultimately  the  body  and  last  pair  of  legs  are  drawn 
out  of  the  shell,  when  the  new  mosquito  flies  away. 
If  during  this  process  there  comes  a  gust  of  wind,  or 
the  water  is  disturbed  in  any  way,  the  mosquito  will 
be  drowned.  It  is  a  fateful  period  of  its  life. 

But  if  there  is  not  enough  food  for  the  three 
hundred  larvae  in  the  water,  they  will  kill  each  other, 


30   LIFE   AND   HABITS   OF   DOMESTIC  MOSQUITOS 

and  only  the  strongest  or  the  luckiest  will  survive  to 
the  pupa  stage.  They  will  sink  all  considerations  of 
family  ties  in  their  desire  to  live  ;  the  strong  ones 
will  eat  up  their  weaker  brothers  and  sisters.  In  the 
meantime,  however,  if  the  mother  returns  to  lay  some 
more  eggs,  the  first  generation  of  children  will  devour 
their  step-brothers  and  sisters.  It  is  extremely  im- 
probable that  both  broods  had  the  same  father- 
male  mosquitos  live  for  only  a  few  hours,  or  at  most 
two  or  three  days;  like  silkworm  moths,  their  lives 
are  just  sufficient  to  ensure  the  perpetuation  of  their 
species. 

It  is  interesting  to  watch  this  cannibalism.  Put 
some  small  mosquito  larvae  into  a  glass  vase  holding 
a  little  clean  filtered  water.  Look  at  it  every  day, 
and  note  how  the  numbers  of  swimming  insects 
decrease,  until  at  last  only  one  or  two  full-grown 
larvae  remain  to  tell  the  tale  ;  but  these  are  well  fed 
and  swollen  at  the  expense  of  their  brethren — they 
have  eaten  them  all.  This  cannibalism  occurs  only 
as  a  last  resource. 

Domestic  mosquito  larvae  and  pupae  have  many 
enemies.  Chief  of  these  are  the  gold-fish.  An  orna- 
mental garden  fountain  which  contains  gold-fish  is 
always  clear  of  mosquitos  ;  the  fish  eat  the  eggs  as 
they  are  laid.  But  all  fish  do  not  eat  mosquito  larvae. 
There  is  a  domestic  species  of  mosquito,  Acartomyia 
zamittii,  that  passes  its  larval  metamorphosis  in  very 
salt  water,  such  as  is  found  in  the  salt-pans  on  the 
seashore  at  Malta,  Beyrout,  Smyrna,  and  on  the 
Mediterranean  littoral  generally.  In  the  pools  where 


THE    LARVA'S    ENEMIES  31 

these  larvae  are  found  there  are  sometimes  small 
fish  ;  but  the  larvae  thrive  notwithstanding. 

Then  there  is  an  insect  that  inhabits  some  fresh- 
water pools  and  ponds.  It  is  known  as  the  water- 
boatman  or  "  backs wimmer  "  (Notonecta).  It  lives  on 
mosquito  larvae,  and  will  keep  a  pond  quite  clear  of 
them.  It  swims  on  its  back  under  the  water  with 
its  face  upwards,  and  catches  the  breathing  mos- 
quito larva  or  pupa  in  its  jaws.  It  is  fitted  with  a 
pair  of  paddles  which  enable  it  to  dart  about  rapidly 
in  the  water  ;  and  it  can  hop  from  one  puddle  to 
another.  It  is  a  water-beetle,  but  is  rendered  power- 
less against  mosquito  larvae  when  the  pond  becomes 
full  of  green  weed,  which  hampers  its  movements. 

Mosquito  larvae  will  not  withstand  drying.  Pour 
some  water  containing  larvae  on  to  some  dry  sand. 
Note  how  the  larvae  soon  stop  wriggling  as  the  water 
dries  up,  and  how  soon  they  die.  They  will  not  live 
in  quickly  running  water  either,  for  there  they 
cannot  breathe.  If  the  wind  causes  a  constant  ripple 
on  the  surface  of  the  water,  they  cannot  breathe, 
and  soon  die  off. 

Mosquito  larvae  have  several  artificial  enemies 
also.  As  stated  before,  they  require  air  to  breathe  ; 
they  must  rise  to  the  surface  of  the  water  every  few 
minutes  to  obtain  the  necessary  supply  of  oxygen. 
Now,  if  the  surface  of  the  water  is  covered  with  a 
layer  of  oil,  the  supply  of  oxygen  is  cut  off.  The  larva 
then  attempts  to  thrust  the  tube  in  its  tail  out  of 
the  water,  but  it  encounters  only  oil.  As  a  result  it 
dies  of  suffocation.  This  artificial  enemy,  which  was 


32   LIFE   AND   HABITS   OF   DOMESTIC  MOSQUITOS 

discovered  by  Aaron  in  America  in  1890,  is  made  use 
of  largely  to  prevent  the  larvae  coming  to  maturity, 
and  is  thus  a  means  of  reducing  mosquitos.  A 
simple  experiment  will  show  how  the  oil  acts.  Place 
a  little  water  containing  mosquito  larvae  into  a 
tumbler,  and  watch  them  wriggling.  Then  put  a  few 
drops  of  any  oil  on  to  the  surface  of  the  water,  and 
wait  until  it  spreads  evenly.  Note  how  each  mos- 
quito larva  rises  to  the  surface  to  breathe,  and  how 
it  tries  to  thrust  its  breathing-tube  through  the 
layer  of  oil — but  its  efforts  are  in  vain.  In  half  an 
hour  all  the  mosquito  larvae  will  be  dead  at  the 
bottom  of  the  water.  This  discovery  has  been  one 
of  the  many  that  have  led  to  the  saving  of  human 
lives. 

Other  artificial  larvicides  have  been  employed. 
An  attempt  has  been  made  to  posion  all  water  con- 
taining mosquito  larvae  with  sulphate  of  copper  or 
lime.  But  the  former  is  very  poisonous,  and  can 
only  be  used  in  cesspools  and  such-like  places,  and 
the  latter  forms  a  hard  calcareous  mass  in  the  water  ; 
both  are  less  efficient  and  more  expensive  than  oil. 
Placing  iron  nails  into  water  cisterns  is  not  much 
better.  Professor  Ross  has  recently  suggested  the 
use  of  cyanide  of  potassium.  It  is  very  poisonous, 
of  course,  but  it  can  be  made  up  into  soluble  tablets 
and  thrown  into  cesspools  or  water  collections  in 
such  a  quantity  that  it  will  not  hurt  human  beings 
or  animals  even  if  they  were  to  drink  it.  This  use  of 
cyanide  of  potassium  is  only  in  its  experimental  stage. 
Petroleum  is  the  larvicide  that  is  commonly  used. 


6  J 

0>     * 


MALES   AND    FEMALES  33 

The  larval  stages  (the  larval  metamorphosis  in- 
cludes the  pupa  stage)  last  for  twelve  days  in  hot 
weather.  If  the  water  is  cold  the  metamorphosis 
may  be  much  delayed — it  may  continue  for  a  month 
or  more.  But  eventually  the  imago  appears.  When 
the  flying  mosquito  has  emerged  from  the  pupa  it 
flies  slowly  to  the  pool-side,  or  perhaps  rests  upon 
some  floating  object  on  the  way.  It  is  very  feeble  at 
first  and  likes  to  rest  and  feed  on  any  food  it  can  find. 
It  thrusts  its  proboscis  into  the  water  or  into  any 
sodden  floating  matter.  Then  mating  takes  place. 

All  the  larvae  that  have  developed  from  one  egg- 
raft  do  not  reach  maturity  at  the  same  time.     Some 
have  had  more  food  than  others.     Out  of  the  three 
hundred  larvae  that  result  from  the  egg-raft  a  very 
large  proportion  become  male  mosquitos.     If  a  hun- 
dred   Culex   larvae   are   collected,    and    all   of   them 
allowed   to   hatch   into  grown   mosquitos   and   then 
killed  with  chloroform  or  tobacco-smoke  and  exam- 
ined, it  will  be  found  that  the  proportion  of  males  to 
females   is   about   seven   to   one — the   males   of   the 
domestic  species  are  always  the  most  numerous.     But 
if  a  mosquito  net  in  a  bedroom  of  a  house  which  is 
infested   with   mosquitos   is   examined   in   the   early 
morning,  it  will  be  noted  that  there  are  only  one  or 
two  males  and  perhaps  twenty  or  thirty  females  rest- 
ing on  the  curtain.     It  is  easy  to  distinguish  them. 
In  the  domestic  species,  the  males  have  plumed  heads 
— their  antennae  are  bushy  and  their  palps  are  long. 
If  so  many  males  are  hatched  from  the  eggs,  how  is 
it  that  they  disappear  so  rapidly,  or  are  not  found  in 
3 


34   LIFE   AND   HABITS   OF   DOMESTIC  MOSQUITOS 

the  bedroom  ?  The  answer  is  that  male  mosquitos 
live  a  few  hours  only  to  fertilise  the  females,  while 
the  latter  may  live  for  months.  Further,  male  mos- 
quitos do  not  require  blood  for  food. 

Since  there  are  so  many  more  males  than  females, 
it  must  be  very  rare  for  the  female  to  escape  early 
fertilisation.  The  males  remain  near  the  water 
collection  and  catch  the  females  as  soon  as  they  are 
hatched.  With  the  more  rural  species  it  is  different. 
These  are  hatched  out  singly  from  the  more  isolated 
eggs,  and  the  larvae  are  consequently  likely  to  be 
more  widely  separated  in  marshes  and  large  collec- 
tions of  scattered  water.  In  this  case,  one  sees,  on 
hot,  still,  summer  evenings,  swarms  of  males  flying 
over  cultivations  and  gardens.  This  is  done  probably 
to  attract  any  newly  hatched  females  that  may  have 
wandered  or  are  playing  truant.  Coitus  takes  place 
either  on  the  wing  or  when  resting.  One  male  may 
fertilise  several  females  in  succession.  At  each  coitus, 
the  three  spermathecae  of  the  female  are  filled  with 
spermatozoa,  unless  the  mosquitos  are  disturbed  in 
the  act.  These  spermathecse  are  spherical,  inelastic 
chitinous  bodies  situated  in  the  last  abdominal  seg- 
ment of  the  female ;  they  can  just  hold  the  number 
of  spermatozoa  requisite  to  fertilise  all  the  eggs  laid 
in  each  brood.  If  a  female  lays  a  whole  egg-raft  or 
complete  brood,  she  exhausts  all  the  spermatozoa 
within  her  spermathecae  and  then  she  must  again 
cohabit  with  a  male  in  order  to  be  replenished. 
This  is  the  reason  why  males  are  likely  to  remain  in 
or,  resort  to  the  places  where  the  females  commonly 


THE    PERPETUATION    OF    THE    SPECIES        35 

lay  their  eggs.  For  example,  in  houses,  the  males  of 
the  Culecines  are  commonly  found  in  the  water- 
closets.  The  females  are  attracted  there  by  the  seal- 
water,  for  they  know  that  their  children  will  thrive 
therein  ;  and  also  that  as  soon  as  they  have  laid 
their  eggs  the  males  are  ready  to  refertilise  them 
again.  The  eggs  exude  their  larvae  into  the  seal- 
water  of  the  closet,  the  latter  are  washed  down  into 
the  cesspool  where  the  water  is  at  an  even  tempera- 
ture, and  where  there  is  plenty  of  food  for  them  ;  so 
the  perpetuation  of  the  species  is  assured.  As  the 
female  lives  so  much  longer  than  the  male,  her 
second  and  third  fecundations  are  brought  about  by 
the  males  of  succeeding  generations  to  her  own.  This 
is  why  males  remain  near  the  breeding-places,  and 
their  presence  in  a  house  is  a  sure  sign  that  the  larvae 
are  near — probably  in  the  cesspool  of  the  house.  In 
any  tropical  town,  when  a  cesspool  is  opened, 
thousands  of  mosquitos  fly  out.  In  Egypt  these 
cesspools  were  the  chief  breeding-places  for  the 
domestic  mosquitos. 

A  female  mosquito  having  partaken  of  several 
meals  of  blood,  and  having  her  ovaries  full  of  matured 
ova,  goes  in  search  of  some  suitable  water  collection 
where  she  can  lay  her  egg-raft  undisturbed,  and 
where  she  can  be  certain  that  her  larvae  will  thrive, 
She  naturally  returns  to  that  collection  of  dirty 
water  where  she  herself  passed  her  own  larval 
metamorphosis  ;  for  she  knows  that  the  water  will 
be  suitable  for  her  purpose.  After  she  has  laid  her 
eggs,  she  will  find  there  males  of  her  own  species,  but 


36  LIFE   AND   HABITS   OF   DOMESTIC   MOSQUITOS 

of  a  later  generation  to  her  own,  for  her  refertilisation. 
Consequently  it  must  be  realised  that  domestic  mos- 
quitos  will  not  fly  far  from  their  breeding-places,  for 
if  there  is  plenty  of  food  near,  there  is  no  reason  why 
they  should.  It  can  hardly  be  expected  that  mos- 
quitos  will  fly  from  one  part  of  a  town  to  another, 
merely  to  gratify  a  whim  of  geographical  curiosity. 
This  is  a  matter  of  the  greatest  importance,  and  it 
has  been  proved  experimentally,  for  it  has  been  found 
possible  to  prevent  mosquitos  in  one  part  of  a  town 
while  they  continue  unchecked  in  another ;  even 
then  they  will  not  fly  into  the  cleared  district. 

Objections  have  often  been  raised  against  pro- 
posed anti-mosquito  campaigns,  that  mosquitos  will 
fly  in  from  the  uncleared  districts  round  about,  and 
so  render  the  campaign  futile.  This  is  not  true. 
Mosquitos  do  not  fly  far,  for  the  reasons  given  above. 
Limited  campaigns  have  been  instituted  as  an  ex- 
periment in  small  portions  of  large  cities,  and  so  long 
as  they  were  conducted  properly  they  were  success- 
ful. Port  Said  and  Cairo  were  examples  of  this.  If, 
however,  there  happens  to  be  a  swamp  that  is  breed- 
ing mosquitos  outside  a  town,  and  there  is  no  food 
near  which  the  fertilised  mosquitos  can  obtain  readily, 
then  a  few  females  will  find  their  way  into  the  town  ; 
but  their  numbers  will  be  very  small.  An  occasional 
mosquito  is  conveyed  by  trains  and  ships,  but  the 
numbers  never  seriously  affect  a  cleared  district. 
Such  objections  are  only  raised  by  lazy  admini- 
strators. 

To  summarise  :    The  fecundated  female  mosquito 


THE   MOSQUITO'S    ENEMIES  37 

must  return  periodically  to  a  suitable  water  collec- 
tion to  lay  her  eggs,  and  to  find  another  male.  The 
larva  spends  twelve  days  in  the  water.  If  the  mos- 
quitos  in  a  town  are  to  be  reduced  it  is  obvious  that 
this  is  the  time  to  attack  them — when  they  are  in 
the  water  and  can  be  easily  reached.  It  is  very 
difficult  to  try  to  catch  and  destroy  the  flying  insects, 
and  it  is  rarely  necessary  except  in  sudden  outbreaks 
of  yellow  fever.  Flying  mosquitos  can  be  dealt  with 
by  fumigation,  and  the  yellow-fever  patients  must  be 
screened  during  the  early  days  of  illness  ;  but  these 
are  special  measures  to  be  undertaken  against  this 
disease. 

Flying  mosquitos  have  certain  natural  enemies  like 
the  larvae,  but  they  are  rarely  efficacious  in  reducing 
the  numbers  of  the  insects.  The  chief  of  these  are 
birds,  bats,  and  lizards.  Cold  also  kills  numbers  of 
imagines,  while  some  of  the  females  hide  in  dark 
corners  and  warm  rooms,  and  hibernate  throughout 
the  winter.  The  best  and  the  cheapest  method  of 
reducing  domestic  mosquitos  in  a  town  undoubtedly 
is  to  destroy  them  when  they  are  larvae  swimming  in 
the  water. 


CHAPTER    III 

THE    FEVER   CENSUS 

WHEN  public  money  is  spent  on  any  municipal  im- 
provement, after  a  time  people  are  inclined  to  ask  : 
What  are  the  results  ?  This  is  also  the  case  with 
health  measures.  Unless  the  state  of  health  of  the 
town  is  known  before  the  sanitary  reform  is  begun, 
it  will  be  impossible  to  obtain  comparative  statistics, 
and  there  will  be  no  means  of  showing  what  the 
results  are.  This  may  cause  those  responsible  for 
instituting  the  reforms  to  render  themselves  liable  to 
deserved  criticism.  Statistical  results  are  always 
expected,  and  every  effort  should  be  made  to  obtain 
them.  Unless  inquiries  are  made  before  the  reform 
is  started  it  is  very  difficult  to  obtain  correct  figures 
afterwards — and  statistics,  to  be  of  any  value,  must 
be  comparable.  It  is  most  important  that  any 
figures  obtained  at  the  outset  of  an  anti-mosquito 
campaign  should  be  checked  regularly  and  periodic- 
ally with  those  obtained  during  its  progress,  and 
compared  with  them,  and  corrected  so  that  the 
methods  employed  may  be  modified  or  improved 
whenever  necessary  or  practicable.  In  this  way  only 
will  it  be  possible  to  state,  as  numerical  facts,  the 


DISEASE   CAUSES   CLIMATIC   MORTALITY       39 

results    obtained,    and    to    justify    the  expenditure 
incurred. 

The  first  step  to  take  is  to  try  to  find  out  the 
common  diseases  present  in  the  town,  and  their  in- 
dividual prevalence.  The  best  person  to  do  this  is 
the  local  health  officer,  if  there  is  one.  The  medical 
officer  of  health  of  a  town  must  be  already  conver- 
sant with  the  diseases  that  cause  the  death-rate. 
He  is  in  touch  with  all  the  local  medical  practitioners, 
and  has  regular  access  to  the  death  registers  and 
examines  the  death  certificates,  if  there  are  any. 

But  health  officers,  especially  in  warm  climates, 
very  frequently  suffer  from  the  belief  that  their 
duties  consist  solely  in  preventing  and  dealing  with 
epidemics,  and  they  are  often  inclined  to  ignore  those 
endemic  diseases  which  may  and  frequently  do  cause, 
both  directly  and  indirectly,  the  high  death-rate.  A 
hot  climate,  in  itself,  does  not  produce  an  excessive 
mortality  ;  it  is  always  due  to  disease.  For  instance, 
since  mosquitos  have  been  abolished  the  mortality 
at  Rio  is  the  same  as  that  of  Liverpool.  There  is 
another  example.  The  Health  Departments  in  Egypt 
have  spent  £249,000  during  the  past  few  years  on  the 
"  prevention  "  of  plague  by  an  out-of-date  method. 
About  900  cases  of  that  disease  occur  in  a  few 
scattered  villages  every  year  ;  but  in  spite  of  the 
so-called  prevention,  the  disease  continues  as  before. 
On  the  other  hand,  some  thousands  of  children  die  of 
the  effects  of  measles  in  the  cities  of  that  country 
annually.  And  yet  for  this  disease  the  Health  De- 
partment has  not  spent  a  penny  ;  and  in  January 


40  THE   FEVER   CENSUS 

1910  the  same  Department  objected  to  subscribing 
£300  towards  the  anti-mosquito  campaign  at  Port 
Said  which  had  had  excellent  results,  and  which  had 
been  the  means  of  reducing  the  general  death-rate  in 
this  formerly  insanitary  and  unhealthy  town.  The 
reason  given  was  that  the  Egyptian  Government 
could  not  afford  to  fight  endemic  disease,  but  must 
expend  all  its  energies  on  epidemics.  They  had 
already  expended  energy  to  the  amount  of  nearly 
£249,000,  and  the  result  was  nil ;  but  they  refused 
£300  towards  the  upkeep  of  a  result  that  is  well 
known  and  obvious.  These  facts  are  mentioned  here 
because  they  serve  to  show  that  the  fight  against 
diseases  that  are  slow  but  sure  in  their  action  is  not 
always  encouraged  by  those  whose  duty  it  is  to 
wage  the  war.  The  reason  is  that  there  is  less 
credit  to  be  obtained  by  fighting  chronic  and  slowly 
killing  fevers  than  by  dramatically  "  preventing  "  an 
epidemic  of  which  there  was  never  much  danger. 

But  it  is  not  always  easy  to  gauge  the  exact 
amount  of  fever  that  exists  in  a  town  ;  nor  the  exact 
nature  of  that  fever.  Even  the  local  health  officer 
may  find  it  difficult  to  discover  how  many  cases  of 
malaria  occurred  during  any  one  year,  how  many 
persons  had  typhoid,  how  many  dengue,  what  was 
the  incidence  of  simple  continued  fever,  or  of  the 
recently  discovered  three-day  fever.  How  is  he  to 
distinguish  between  them  all  ? 

In  the  present  state  of  our  knowledge  one  cannot 
be  certain  of  doing  this.  It  is  only  possible  to  com- 
pare one  year  with  another — hence  the  importance 


"  FEVER  "  41 

of  comparable  statistics.  If  the  health  officer  can 
compare  the  total  number  of  cases  of  fever  notified 
year  by  year,  before  and  after  the  mosquito  cam- 
paign is  started,  all  well  and  good.  But  he  cannot 
always  even  do  this.  There  are  many  tropical  towns 
— there  are  many  European  towns — in  which  no 
health  statistics  are  or  ever  have  been  kept.  He 
may  have  to  find  out  the  details  of  disease  incidence 
for  himself. 

He  should  examine  the  death  registers,  if  there 
are  any.  He  will  find  that  it  is  diarrhoea  and 
broncho-pneumonia  that  kill  the  most ;  many  infants 
have  died  of  these  two  diseases.  Then  he  will  notice 
that  many  old  people  have  died  of  pneumonia  and 
bronchitis,  apoplexy,  and  dropsy — a  few  of  old  age. 
But  frequently  there  will  be  some  deaths  marked  in 
the  register,  "  Fever  "  ;  and  this  is  especially  notice- 
able in  India.  What  are  these  ?  Are  they  all 
malaria  ?  It  will  lead  him  to  inquire  into  the  ac- 
curacy of  the  methods  of  registration.  This  will 
open  his  eyes.  In  England,  practically  every  death 
that  occurs  is  accompanied  by  a  certificate  signed  by 
either  the  medical  practitioner  who  attended  the 
case  in  the  last  illness,  or  by  the  coroner ;  and  the 
cause  of  death  is  written  on  that  certificate.  But  in 
countries  where  there  are  many  natives  such  certifi- 
cation is  unusual.  Most  of  these  natives  die  without 
medical  attendance — their  relatives  can  rarely  pro- 
duce a  medical  certificate.  It  may  be  the  custom  to 
send  a  doctor  of  the  Health  Department  to  view  the 
corpse  in  order  to  see  that  death  has  not  been  due  to 


42  THE    FEVER    CENSUS 

plague  or  cholera ;  but  this  is  not  much  use,  for  it 
is  difficult  to  say  what  a  man  died  of  by  merely 
looking  at  his  skin.  The  Arab  knows  only  one  cause 
of  death ;  it  is,  "  God  willed  it  that  the  heart  should 
stop."  In  India  one  may  see  in  the  death  register — 
"  Plenty  much  belly  pains."  But  these  are  not  very 
scientific  causes  of  death.  Even  suppose  a  death  is 
certified  as  fever,  it  is  rarely  stated  which  fever. 
Some,  but  not  very  much,  knowledge  can  be  obtained 
from  the  death  registers ;  even  the  little  gained  is 
rarely  reliable. 

The  health  officer  should  apply  to  the  doctors. 
If  there  is  a  local  medical  association  or  institute  he 

•4* 

may  utilise  it  for  the  purpose.  Or  he  may  write  a 
circular  letter  to  all  the  medical  men  practising  in 
the  town,  inviting  them  to  inform  him  of  such  cases 
of  fever  as  come  to  their  knowledge  ;  but  it  is  neces- 
sary to  explain  to  them  the  reason  for  the  demand. 
Experience  shows  that  it  is  better  not  to  make  fever 
a  compulsorily  notifiable  disease.  It  is  very  tire- 
some for  any  medical  practitioner  to  be  constantly 
filling  up  and  posting  notification  forms  ;  in  many 
countries  there  is  no  compulsory  notification.  Then 
a  medical  man  may  notify  a  case  as  fever,  and  it 
turns  out  to  be  appendicitis,  and  he  is  obliged  to 
correct  his  diagnosis  ;  this  gives  him  extra  trouble, 
and  it  vitiates  the  returns.  It  is  better  to  ask  them 
to  send  in  a  biennial  list  of  all  cases  of  "  fever  " — 
other  than  typhoid,  typhus,  Malta  fever,  or  tubercu- 
losis, to  the  health  office.  This  gives  less  trouble  to 
the  practitioner  than  regular  notification.  He  can 


THE    VARIETIES    OF    FEVER  43 

make  up  his  list  from  his  books  when  he  draws  up 
his  accounts.  If  possible,  it  is  a  good  plan  to  have  a 
number  of  forms  typewritten  (or  printed,  if  there  are 
funds  available)  with  columns  dividing  the  fever  in- 
cidence into  three  categories — three-day  fever,  seven- 
day  fever,  and  fever  of  longer  duration.  Under  each 
heading  the  doctor  can  enter  the  number  of  cases 
treated  by  him  which  come  under  these  categories. 
One  of  such  forms  can  be  sent  to  each  practitioner 
at  every  half-year,  or  just  before  each  quarter-day,  as 
convenient  to  them. 

The  books  of  the  hospital  and  dispensaries  should 
be  examined.  Much  valuable  information  can  be 
obtained  in  this  way.  A  clerk  can  easily  count  the 
number  of  in-patients  treated  for  "  fever  "  during 
five  years.  He  must  exclude  typhoid  and  the  others, 
and  he  can  place  malaria  and  yellow  fever  in  another 
list.  Then  he  can  obtain  the  bed  tickets  and  tem- 
perature charts  of  those  patients  who  suffered  from 
fever,  from  the  registrar  or  secretary.  These  may  be 
sorted  out  and  separated  into  groups  similar  to  those 
mentioned  above — namely,  three-day,  seven-day,  and 
longer  fever.  The  out-patient  and  dispensary  books 
also  will  probably  show  a  number  of  cases  marked  as 
"  fever."  This  diagnosis  may  include  early  typhoid, 
malaria,  measles,  influenza,  and  many  other  affections, 
but  still  the  figures  obtained  may  be  useful  for  com- 
parison in  future  years.  But  in  all  cases  it  is  im- 
portant to  note  at  the  same  time  the  total  number 
of  cases  treated  every  year  both  as  in-patients  and 
out-patients ;  then  the  sick-rate  can  be  obtained. 


44  THE   FEVER   CENSUS 

Some  doctors  dislike  imparting  information  concern- 
ing the  total  number  of  patients  treated  by  them, 
and  their  wishes  in  this  should  be  respected.  The 
percentages  obtained  from  the  hospital  and  dispen- 
sary records  do  not  suffer  from  this  disability.  There 
will  soon  be  a  list  showing  that  out  of  a  number  of 
sick  persons  treated  in  the  town  there  were  so  many 
that  had  suffered  from  "  fever,"  and  these  cases  of 
"  fever  "  are  classified. 

Similar  inquiries  should  be  made  from  the  em- 
ployers of  regular  labour.  From  factories,  work- 
shops, dock-boards,  stores,  municipal  stables,  police 
barracks,  offices — anywhere  where  a  number  of 
people  are  employed.  The  owners  and  managers  of 
such  establishments  and  organisations  must  be  ap- 
proached carefully,  however.  They  are  very  liable 
to  become  frightened  at  the  approach  of  the  health 
authority  ;  and  their  fright  will  exhibit  itself  in  re- 
ticence. They  will  not  hesitate  to  make  exaggerated 
statements  concerning  the  health  or  the  reverse  of 
their  workpeople,  if  they  think  it  will  be  an  adver- 
tisement, or  will  save  trouble.  For  example,  the 
manager  of  an  hotel  will  rarely  speak  out  about  the 
health  of  its  visitors.  So,  too,  with  the  manager  of 
a  workhouse,  or  the  director  of  a  reformatory  or 
prison.  The  health  officer  must  be  tactful  in  such 
matters,  or  he  will  find  a  closed  door.  It  is  better 
to  deal  with  the  medical  advisers  to  such  establish- 
ments if  he  can.  If  this  is  not  possible,  he  must 
first  advertise  his  reasons  for  making  the  inquiries. 
Let  him  put  a  notice  in  the  local  newspaper  asking 


AMONG  CHILDREN  AND  OTHERS      45 

people  to  co-operate  with  him.  If  a  thought  of  the 
General  Medical  Council,  or  similar  body,  raises  a 
quake  of  fear  in  his  mind,  let  the  notice  in  the  journal 
emanate  from  the  secretary  to  the  municipality  or 
some  such  corporation.  Anyhow,  let  his  intention  be 
advertised.  People  will  largely  co-operate  if  they  see 
the  sense  and  sincerity  of  the  purpose. 

Lastly,  let  him  inquire  at  the  schools.  Each 
school  should  be  visited.  How  many  scholars  are 
there  ?  How  many  attend  regularly  ?  How  many 
are  absent  during  the  year,  and  for  how  many  days^? 
At  what  time  of  the  year  are  the  absentees  the  most 
numerous  ?  Remember  that  the  masters  of  private 
schools  may  extol  the  healthy  condition  of  his  pupils. 
It  is  better  to  examine  the  books,  if  possible.  Why 
in  one  school  are  there  more  children  absent  than  in 
another  ?  This  is  the  subject  for  his  inquiry.  Have 
they  had  fever  ?  If  so,  what  fever  ?  It  is  guaran- 
teed that  the  health  officer  will  soon  learn  matters 
that  he  never  realised  before  concerning  the  health  of 
his  town.  In  all  cases  let  the  figures  be  written  down, 
and  carefully  kept. 

There  will  soon  be  a  collection  of  interesting  ob- 
servations that  may  be  correlated.  The  population 
of  the  town  is  known.  Inquiries  have  been  made 
concerning  a  number  of  persons  of  both  sexes,  of  all 
ages  and  degrees  of  life,  of  schoolchildren,  policemen, 
labourers,  and  workgirls  ;  and  of  these  so  many  have 
had  fever  of  some  nature  or  other  during  some  period 
of  the  year.  Then  the  doctors  will  give  him  the  lists 
showing  the  number  of  sick  people  treated  by  them. 


46  THE   FEVER   CENSUS 

that  suffered  from  fever  of  various  kinds.  In  this 
way  the  percentages  of  fever  incidence  can  be  ob- 
tained. These  percentages  can  be  checked  by  the 
figures  obtained  from  the  hospital  and  dispensaries. 
If  the  inquiries  have  concerned  a  sufficient  number  of 
persons,  there  will  only  be  such  a  small  statistical 
error  that  it  can  be  ignored ;  but  this  error  may  always 
be  discovered  by  the  Pearson-Poisson  formula — a 
formula  that  is  well  known  to  all  students  of  vital 
statistics. 

But  how  is  it  possible  to  discover  the  exact  nature 
of  the  fevers  that  occur  in  the  town  ?  How  can  it  be 
known  that  any  of  them  are  conveyed  by  mosquitos  ? 
It  may  be  stated  that  this  question  cannot  be  answered 
at  once  in  the  present  state  of  knowledge.  Fevers  in 
warm  climates  have  not  yet  been  completely  classified. 
The  returns  will  include  all  sorts  of  fevers  of  various 
origin.  But  if  the  figures  obtained  before  the  mos- 
quito campaign  begins  are  compared  with  those 
obtained  from  the  same  sources  and  in  precisely 
the  same  way  afterwards,  when  the  mosquitos 
have  disappeared  from  the  town,  a  difference  will 
be  noticed — a  marked  difference.  If  the  campaign  is 
carried  out  properly,  the  mosquitos  will  disappear 
rapidly ;  but  the  fevers  will  disappear  even  more 
rapidly. 

If  there  is  no  health  officer,  an  official  may  be 
appointed  by  the  municipality  or  any  local  authority, 
or  even  a  community  of  residents,  to  undertake  the 
mosquito  campaign,  and  to  carry  out  the  fever  cen- 
sus. A  medical  man  is  the  best  person  to  do  this,  of 


A    PUBLIC   DUTY  47 

course,  but  it  is  not  absolutely  essential.  In  a  small 
community,  any  responsible  person  who  has  the 
sympathy  of  his  fellow  villagers  can  undertake  the 
measures  recommended  in  this  book. 

If,  when  making  the  fever  census,  it  is  discovered 
that  there  is  actually  malaria  in  the  town,  then  a 
spleen  census  must  be  taken,  and  the  disease  stamped 
out  as  promptly  as  possible ;  the  methods  are  fully 
described  in  Professor  Ross's  book,  "  The  Prevention 
of  Malaria."  Or  if  there  is  yellow  fever,  Sir  Rubert 
Boyce's  "  Mosquito  or  Man  "  gives  all  the  informa- 
tion required  for  fumigation  and  isolation,  and  for 
successfully  dealing  with  the  disease. 


CHAPTER    IV 

THE   ESTIMATE   OF   THE    COST 

REFORMS  of  almost  all  kinds  cost  money,  and  sani- 
tary reforms  are  no  exception  to  this  rule.  But  as 
health  is  cheap  at  any  cost,  the  extra  expenditure  is 
well  justified  when  a  mosquito  campaign  is  proposed. 
Unnecessary  extravagance,  however,  must  be  avoided. 
Mosquito  reduction  is  not  an  expensive  measure,  but 
it  cannot  be  done  for  nothing.  Some  money  will  be 
required  ;  and  the  question  is — How  much  ? 

The  cost  varies  in  different  localities  and  is  de- 
pendent upon  several  variables.  Thus,  the  size  and 
population  of  the  town  or  village,  and  the  size  and 
congestion  of  the  houses.  Then  the  presence  of  cess- 
pools and  their  individual  extent,  the  efficiency  of 
any  sewers  and  street  drains,  the  means  of  storing 
water  in  houses  in  water-butts  or  cisterns,  and  the 
presence  or  absence  of  rain  in  the  hot  weather.  In 
addition  to  these,  the  important  factors  are  the  price 
of  labour  and  the  cost  of  oil. 

The  influence  of  these  variables  is  well  shown  by 
the  difference  in  the  cost  of  the  mosquito  campaigns 
in  the  two  neighbouring  towns  of  Port  Said  and 
Ismailia.  In  the  former  the  cost  is  only  sixpence  per 

48 


ROUGH   METHOD    OF   CALCULATION  49 

head  of  population  per  year,  while  in  the  latter  it  is 
nearly  two  shillings.  This  difference  is  largely  due  to 
the  many  regularly  irrigated  gardens  at  Ismailia, 
which  have  to  be  dealt  with  every  week.  But  the 
comparative  size  of  the  two  towns  is  also  an  im- 
portant factor  in  producing  the  difference  in  the  cost 
of  the  two  campaigns.  It  may  be  taken  as  a  general 
rule  that  the  larger  the  town,  the  less,  relatively,  is 
the  cost  per  head  of  population  per  year  ;  and  at  the 
same  time,  the  more  scattered  the  houses,  the  greater 
becomes  the  annual  cost  of  the  work.  Thus  Port 
Said  is  a  compactly  built  town  of  50,000  inhabitants, 
whose  houses  are  closely  packed  together,  while 
Ismailia  is  an  openly  built  village  of  10,000  people 
only. 

In  dry  summer  climates,  such  as  that  of  the 
Mediterranean  littoral,  it  may  be  accepted  that  a  cam- 
paign against  domestic  mosquitos  will  cost  £1,000  a 
year  for  each  50,000  inhabitants  in  towns  having  less 
than  250,000  population.  In  towns  having  less  than 
25,000  inhabitants  the  cost  will  be  relatively  greater, 
while  in  those  over  250,000  it  will  be  relatively  much 
less  ;  but  the  scale  is  a  geometrical  one,  and  cannot 
be  estimated  in  arithmetical  proportion.  However, 
a  municipal  rate  of  sixpence  per  head  of  population 
per  year  should  be  sufficient  for  the  upkeep  of  a  mos- 
quito campaign  in  towns  and  cities  having  a  popula- 
tion of  more  than  25,000  inhabitants  ;  but  this  rate 
may  have  to  be  increased  owing  to  summer  rains  or 
floods,  where  there  is  no  drainage  or  outflow  for  the 
water  over  an  impermeable  soil,  or  if  there  is  much 
4 


50  THE   ESTIMATE    OF   THE   COST 

irrigated  land,  many  parks  and  public  gardens, 
birkets  or  large  ponds.  On  the  other  hand,  it  may  be 
decreased,  as  stated  before,  by  a  well-arranged  drain- 
age system,  provided  that  the  flush  is  ample  and 
constant.  Shortly,  if  there  is  much  water  that  re- 
mains stagnant  for  more  than  a  week  at  a  time,  the 
cost  of  the  domestic  mosquito  campaign  will  be 
proportionately  greater. 

The  estimate  given  above  does  not  include  major 
sanitary  works,  such  as  the  filling  in  of  marshes,  pools, 
borrow-pits,  birkets,  and  such-like  collections  of  water 
suitable  for  mosquito  breeding-places — the  cost  of 
such  measures  must  vary  considerably  in  different 
countries  ;  but  the$e  are  ordinary  sanitary  measures 
and  should  not  be  placed  to  the  account  of  the  mos- 
quito work  alone,  as  has  so  often  been  done.  It  is  a 
mistake  to  include  such  municipal  expedients  in  the 
budget  for  the  mosquito  campaign,  for  then  com- 
mittees are  liable  to  dismiss  the  whole  project  on 
account  of  its  great  initial  cost,  forgetting  that  it  is 
the  duty  of  the  State  to  undertake  permanent  reforms 
that  lead  to  health.  The  estimate  given  above  is  for 
the  upkeep  only  of  a  regular  anti-mosquito  campaign, 
and  large  town-planning  schemes  must  not  be  in- 
cluded. 

Such  an  estimate  is,  at  best,  a  rough  one.  It  is 
better  to  make  a  careful  house-to-house  examination 
of  the  town,  noting  exactly  where  the  mosquitos  are 
breeding,  and  estimating  directly  the  cost  of  dealing 
with  them.  It  is  not  a  very  great  undertaking,  and 
will  well  repay  the  energy  expended.  Take  a  survey 


••JJr'-V  M 

/.**.*  ..  R 


Plan  of  breeding-places  of  domestic  mosquitos  at  New  Orleans. 

(After  Boijce.) 


[P.  51 


EXACT   METHOD    OF    CALCULATION  51 

map  of  the  town — if  one  cannot  be  obtained,  make  a 
sketch-map — and  rule  it  into  squares.  The  squares 
should  be  of  equal  extent  as  far  as  possible,  and  their 
total  should  include  the  whole  area  to  be  dealt  with. 
Begin  at  one  corner  and  examine  all  the  houses  in 
each  square  street  by  street.  Write  in  a  large  note- 
book the  name  of  the  streets  and  the  number  of  each 
house  or  hut,  if  they  are  numbered.  If  there  are  no 
numbers  or  names,  write  the  name  of  the  proprietor 
of  each  house  and  a  tenant.  This  examination  should 
be  made  during  the  height  of  the  mosquito  season, 
and  immediately  after  heavy  summer  rains,  so  that 
the  estimate  may  be  made  during  the  period  of 
maximum  density  of  the  insects.  During  this  ex- 
amination a  careful  inspection  must  be  made  of  all 
backyards,  and  every  cesspool  should  be  opened. 
The  presence  or  absence  of  mosquitos  or  their  larvae 
should  be  noted,  and  the  extent  of  the  water  surface 
which  contains  them.  The  number  of  garden  foun- 
tains, water-butts,  cisterns,  ponds,  garden  puddles 
and  pools  should  be  counted,  and  the  presence  of 
mosquito  larvae  or  pupae  in  them  observed  and 
written  down. 

At  the  end  of  the  house-to-house  examination  of 
the  town  the  number  of  square  metres  of  water  sur- 
face can  be  added  together — a  water-butt  may  be 
estimated  as  having  half  a  square  metre  of  water 
surface.  Then,  allowing  one  litre  of  mixed  oil  for 
each  square  metre  of  water  surface  per  week,  and 
multiplying  by  fifty-two,  the  exact  estimate  of  the 
amount  of  oil  required  per  year  will  be  obtained. 


52  THE    ESTIMATE    OF   THE    COST 

The  best  larvicide  for  mosquitos  is  the  aboli- 
tion and  prevention  of  stagnant  water  collections  ; 
but  the  second  best  is  the  use  of  oil.  Cesspools 
should  be  replaced  by  a  sewerage  ;  local  marshes 
ought  to  be  drained,  or  filled  up  and  reclaimed  ;  in- 
filtration water  collections  levelled  ;  and  house-tanks 
and  water-butts  dispensed  with  by  a  better,  or  more 
constant,  pressure  of  water  on  the  town  mains.  But 
while  such  municipal  reforms  are  being  carried  out 
or  discussed,  the  reduction  of  mosquitos  may  be  con- 
ducted by  the  use  of  oil  as  a  larvicide. 

The  oil  most  commonly  used  for  this  purpose  is 
petroleum.  In  Egypt  equal  parts  of  refined  and 
crude  petroleum  mixed  together  is  generally  used. 
As  a  matter  of  fact,  any  oil  may  be  employed,  as 
already  pointed  out,  for  it  is  the  mechanical  action 
of  the  oil  resting  on  the  surface  of  the  water  in  an 
even  layer  that  suffocates  the  mosquito  larvae,  and 
not  any  poisonous  effects.  But  petroleum  is  usually 
the  cheapest,  and  the  oil  commonly  used  for  this 
reason  ;  it  is  also  obtainable  everywhere.  But  even 
petroleum  is  expensive  when  used  in  large  quantities. 
Its  cost  varies  in  different  countries,  and  in  different 
localities  of  the  same  country.  For  example,  at  Cairo 
the  mixed  oil  costs  sixpence  per  gallon,  at  Port  Said 
it  is  a  trifle  less.  When  the  mosquito  campaign  was 
first  started  in  the  latter  town,  the  crude  oil  was  more 
expensive  than  the  refined,  because  the  latter  was 
imported  "  in  bulk  "  in  tank  steamers,  while  the 
crude  petroleum  was  only  brought  from  the  East 
Indies  in  small  quantities  at  a  time,  and  the  freights 


"OIL"    AND    "LABOUR"  63 

were  high  ;   as  it  came  more  in  demand,  however,  its 
price  fell  somewhat. 

But  if  it  is  known  how  much  oil  is  required  per 
year,  an  estimate  can  be  demanded  from  the  various 
local  merchants,  and  the  lowest  tender  accepted.  If 
there  is  any  cheaper  kind  of  oil  on  the  market  it  may 
be  employed  as  the  larvicide.  "  Elephant  oil  "  is 
quite  efficacious  as  a  mosquito  larvicide,  but  it  is 
liable  to  become  thick  in  cold  weather,  and  will 
require  mixing  with  such  a  large  quantity  of  refined 
petroleum  in  order  to  spread  well  on  the  water,  that 
there  is  little  or  no  saving  of  money. 

Facilities  for  the  supply  of  oil  can  be  obtained  in 
every  town,  but  in  some  countries  the  presence  of  oil 
depots  are  prohibited  near  dwellings.  In  this  case 
allowance  must  be  made  in  the  estimate  for  the 
regular  transport  into  the  town  every  day  or  every 
week  as  convenient. 

The  amount  of  oil  required  per  year  and  its  cost 
having  been  estimated,  the  next  thing  to  do  is  to 
count  the  number  of  days  which  were  required  to 
make  the  house-to-house  examination  of  the  town  by 
one  person.  From  this  it  is  readily  calculated  how 
many  men  will  be  required  to  visit  similarly  every 
house  and  garden  in  the  town  once  every  week, 
excluding  Sundays.  Then,  the  price  of  local  labour 
being  known,  the  annual  cost  of  the  number  of  work- 
men required  can  be  readily  determined.  If  the  town 
is  a  large  one  these  workmen  should  be  divided  into 
gangs,  each  controlled  by  an  overseer  or  foreman. 
Each  gang  should  consist  of  three  or  four  men,  and 


54  THE    ESTIMATE    OF   THE    COST 

their  work  distributed  fairly  and  evenly.  The  usual 
pay  of  such  men  can  be  found  out  by  application  to 
any  large  employment  contractor  or  agency. 

The  cost  of  the  oil  likely  to  be  required  per  year 
will  thus  be  known,  and  also  the  cost  of  labour  and 
the  necessary  staff.  It  only  remains  to  estimate  the 
price  of  one  oil  cart  for  each  gang,  overalls  for  the 
men,  and  to  make  allowance  for  repairs,  and  for  sick- 
ness among  the  foremen,  etc. 

In  this  way  exact  estimates  for  an  urban  mosquito 
campaign  should  be  drawn  up.  If  there  are  many 
constant  rain-water  puddles  in  which  the  water  com- 
monly remains  stagnant  for  more  than  a  week,  and 
these  cannot  be  readily  drained  or  filled  up,  provision 
must  be  made  in  the  estimates  for  dealing  with  them 
regularly,  like  other  permanent  water  collections. 
Mosquitos  require  at  least  twelve  days  in  water  to 
pass  their  larval  metamorphosis  even  in  the  hottest 
weather,  and  the  mosquito  larvae  will  not  stand  dry- 
ing ;  this  knowledge  must  always  be  borne  in  mind 
when  the  question  of  collections  of  rain-water  is  being 
dealt  with. 

As  stated  before,  this  method  of  making  the  esti- 
mate is  not  a  very  great  undertaking  ;  and  there  is 
the  satisfaction  of  knowing  that  it  is  correct,  and 
that  there  will  be  little  likelihood  of  the  necessity  for 
subsequent  requests  for  further  grants.  If  there  is 
any  doubt  on  this  point  it  is  better  to  make  an 
estimate  in  excess,  for  constant  demands  for  supple- 
mentary credits  are  always  a  source  of  annoyance  to 
administrators  and  councils. 


v 


CHAPTER    V 

WAYS   AND    MEANS 

THE  fever  census  having  been  taken,  and  the  cost  of 
the  projected  domestic  mosquito  campaign  estimated, 
it  remains  to  find  the  money  to  start  and  to  defray 
the  regular  upkeep  of  the  work.  The  question  arises 
at  once — Who  is  to  pay  ? 

It  is  the  duty  of  that  organisation  of  the  com- 
munity that  safeguards  the  public  health  to  institute, 
and  to  maintain,  all  measures  that  will  improve  the 
condition  of  the  people  of  the  community.  The  neces 
sary  means  must  be  supplied  by  the  local  authority 
of  the  State — for  this  is  the  business  of  the  State. 
But  it  must  also  be  brought  home  to  such  organisa- 
tions that  such  measures  are  necessary  ;  otherwise 
the  local  authority  will  object  to  the  expenditure  of 
the  public  money — and  rightly,  for  it  is  also  the 
guardian  of  the  public  purse. 

The  health  officer  should  draw  up  a  report.     It 
should  give  details  of  the  death-rate,  of  the  sickness- 
rate,  and  of  the  prevalence  of  fever  as  obtained  by 
the  fever  census.     Then  the  prevalence  of  mosquitos  , 
in   the   town   should   be   described   and   their  chief  > 
breeding-places,  and  the  proposed  method  of  dealing  • 

55 


56  WAYS    AND    MEANS 

with  them.  The  probable  results  should  be  outlined 
Ynd  the  work  done  elsewhere  described.  The  brilliant 
results  obtained  in  the  rainy  Federated  Malay  States, 
on  the  Panama  Canal,  or  the  almost  rainless  Suez 
Canal  and  Khartoum  can  safely  be  quoted.  The 
estimated  cost  should  be  set  forth  and  the  report 
should  be  printed  and  circulated.  It  will  not  be  a 
costly  matter,  and  the  local  health  office  can  usually 
find  means  for  doing  this.  Or  it  can  be  typed,  or 
even  written  if  the  town  is  a  small  one,  and  then 
sent  round  to  all  the  influential  citizens.  If  there  is 
an  urban  council  of  any  kind,  each  member  should  be 
supplied  with  a  copy,  and  the  local  journal  convened 
to  assist. 

If  there  is  no  local  authority  which  can  supply  the 
necessary  funds,  recourse  must  be  had  to  public  sub- 
scription, unless  some  private  corporation  is  willing 
to  undertake  the  work  for  a  charitable  purpose.  But 
to  pay  for  an  established  public  reform  by  an  inter- 
mittent general  subscription  is  always  an  unsatisfac- 
tory proceeding ;  and  to  leave  it  in  the  hands  of 
charity  is  immoral.  The  work  is  to  be  done  for  the 
good  of  the  whole  community,  and  it  should  be  paid 
for  by  that  community. 

The  State  then  must  produce  the  necessary  funds, 
and  it  probably  will  do  so  if  approached  in  the  right 
way.  If  the  report  is  drawn  up  well,  and  the  idea  is 
backed  by  influential  persons,  the  State  can  hardly 
refuse  its  support.  If  it  does  refuse,  such  a  refusal 
will  be  based  on  the  plea  of  economy.  But  the  plea 
of  economy  is  a  poor  pill  to  give  a  sick  town,  and  few 


•NiV,    OF 

CALIF:    -, 


TOWN 

OF 


•\   PORT  SWETTENHM 


p.  56] 


Port  Swettenham  in  the  Federated  Malay  States.     Now  cleared 
of  mosquitos  and  healthy. 

(After  Watson.) 


HEALTH    A  CREDITABLE   ASSET  57 

such  towns  will  tolerate  it  for  long.  If  the  State 
refuses  to  do  its  duty  to  the  public  it  will  soon  become 
unpopular ;  an  unpopular  Administration  does  not 
last.  These  are  points  to  be  remembered,  and  efforts 
should  be  made,  if  necessary,  to  impress  their  im- 
portance on  backward  corporations,  Government 
departments,  etc. 

There  is  rarely  necessity  for  such  hints,  however, 
and  the  money  will  be  forthcoming  if  the  demand  is 
reasonable,  persistent,  and  sensibly  made.  If  the 
estimate  is  carefully  drawn  up,  and  the  desire  to  do 
the  work  sincere,  the  necessary  means  will  soon  appear. 
Financiers  are,  perforce,  sensible  people,  and  they 
like  to  be  assured  of  some  return  for  their  money. 
Suppose  a  corporation  of  a  town  is  invited  to  vote 
£1,000  a  year  in  order  to  reduce  mosquitos,  it  will 
naturally  ask  what  the  return  will  be.  The  long- 
vexed  question  of  municipal  trading  has  been  settled 
in  its  favour,  and  local  governing  bodies  like  to  be 
able  to  report  that  such-and-such  a  public  work  has 
brought  in  such-and-such  a  percentage  on  the  capital 
expended.  £1,000  per  year  represents  a  capital  of 
over  £30,000  which  must  be  set  aside  for  this  mosquito 
work.  Where  is  the  dividend  ?  How  much  per  cent 
is  it,  and  when  will  it  be  paid  ?  What  is  the  return  ? 
These  are  the  questions  that  will  at  once  arise. 

The  same  financiers  will  say  that  credit  is  almost 
as  good  as  an  actual  asset — by  some  it  is  considered 
more  useful.  A  town  with  a  bad  name  for  being 
unhealthy  has  no  asset,  and  it  has  no  credit.  It  has 
no  trade,  there  is  no  business  going  on — people  who 


58  WAYS    AND    MEANS 

live  in  it  are  always  ill — there  is  nothing  doing,  and 
its  population  will  not  increase,  no  matter  what  its 
position  or  its  natural  advantages  may  be.  Nobody 
will  invest  money  there  for  building  or  trading,  for 
tramways  or  amusements  ;  and  the  place  will  soon 
be  at  a  standstill.  It  commands  no  credit,  and  it  has 
no  asset — it  is  unhealthy.  But  if  the  town  is  made 
healthy,  then  money  will  soon  flow  in,  and  its  credit 
will  advance  and  become  cheaper  as  progress  replaces 
the  condition  of  standstill.  Then  the  expenditure 
will  be  justified,  and  the  sunken  capital  will  not  be 
grudged  or  cavilled  at.  These  truisms  must  be  em- 
phasised ;  the  results  obtained  at  Havana,  Rio,  and 
New  Orleans  can  be  quoted  with  assurance. 

But  should  it  be  found  impossible  to  obtain  funds 
from  the  State,  a  public  subscription  must  be  raised. 
Then,  if  the  work  is  successful,  the  State  can  again  be 
approached  to  take  up  its  share  of  the  burden.  How- 
ever, as  mentioned  before,  public  subscripton  is  not 
very  satisfactory.  Public-spirited  persons  will  suby 
scribe  for  a  time.  They  may  find  mosquitos  a  terrible 
pest  in  their  houses,  or  they  may  find  their  children 
constantly  ill,  or  their  occupations  suffering  through 
their  ill-health,  or  the  constant  sickness  of  their  em- 
ployees may  be  costing  them  money  or  hurting  trade  ; 
then  they  will  subscribe.  But  a  time  will  come,  after 
the  mosquitos  have  disappeared,  and  are  forgotten, 
when  the  subscribers  will  fail  in  their  support  of  the 
cause,  or  a  new  generation  will  grow  up  that  knew 
not  mosquitos,  and  it  will  not  pay.  At  first  they  will 
forget  to  subscribe,  then  they  will  grumble,  and  at 


A    LAST   ALTERNATIVE  59 

last  they  will  refuse  ;  and  the  mosquitos  will  surely 
return.  But  it  is  most  disappointing  and  may  be 
heartbreaking,  for  all  the  trouble  and  energy  expended 
will  be  for  nothing  ;  but  not  quite,  for  something  will 
be  learnt  from  the  lesson.  Perseverance  and  again 
perseverance — this  must  be  the  motto  always.  Begin 
again,  and  try  the  State  once  more. 

If  subscription  is  the  only  course  that  can  be 
adopted,  it  can  best  be  carried  out  in  the  following 
way.  Advertise  in  every  direction  the  nature  of  the 
work  to  be  started.  Institute  public  lectures,  dis- 
tribute fly-leaves  describing  what  is  going  to  be  done,, 
the  reason  for  it,  the  estimated  cost,  and  the  probable 
results.  Talk  about  it  to  influential  persons,  and 
prove  the  sincerity  of  the  purpose.  Then  open  a  sub- 
scription list  at  the  banks  and  post  offices.  Get  up 
a  fete  or  a  ball  or  a  theatrical  performance  on  its 
behalf.  Write  to  the  local  papers.  Interest  the 
large  trading-houses,  the  doctors,  the  local  exploiting 
companies,  the  schoolmasters,  the  clergy.  Keep 
open  the  subscription,  and  canvass.  It  is  worth  it. 
There  can  be  no  better  charity  than  this.  But  let 
very  careful  accounts  of  money  received  and  ex- 
pended be  kept.  Balance  sheets  must  be  published 
regularly,  and  the  names  of  the  subscribers  and 
their  subscriptions  registered,  so  that  the  same  may 
be  applied  to  again  and  the  results  reported  to  them. 

Public  subscription  is  a  course  that  is  not  advised 
unless  it  is  found  impossible  to  raise  the  necessary 
means  in  any  other  way.  Therefore  it  should  only 
be  regarded  as  a  final  resort.  Mosquito  reduction  is 


60  WAYS    AND   MEANS 

such  a  boon  and  a  blessing  to  the  whole  community, 
and  as  it  is  one  of  the  most  popular  of  all  sanitary 
measures,  the  money  can  generally  be  found  for  it  if 
sufficient  energy  is  expended  in  propounding  its  pos- 
sibilities, and  a  real  effort  is  made  to  carry  it  out.  It 
has  been  successful  elsewhere,  and,  if  properly  con- 
tinued, it  never  fails. 


CHAPTER    VI 

PRELIMINARIES 

WHEN  the  estimate  is  approved,  and  sufficient  money 
for  the  start  has  been  found,  the  first  preliminary  is 
to  state  publicly  the  nature  of  the  work — the  reason 
why  it  is  to  be  adopted,  the  method  to  be  followed, 
and  the  result  it  is  hoped  to  obtain.  This  is  best  done 
in  the  local  newspapers.  It  should  be  advertised  that 
the  intention  is  to  reduce  the  number  of  mosquitos, 
and  with  them  the  incidence  of  fevers.  Ask  for  the 
general  co-operation  of  the  public.  Then  write  again 
and  describe  how  the  work  is  to  be  carried  on  con- 
tinuously. Relate  how  mosquitos  breed,  and  pass 
their  larval  lives  in  dirty  water  ;  how  it  is  proposed 
to  reduce  the  numbers  of  the  insects  by  attacking 
them  during  their  lives  in  the  water.  Describe  the 
methods.  There  must  be  no  mystery  about  it.  Ask 
boldly  for  permission  to  enter  every  house  in  the  town 
once  every  week  for  the  purpose  of  killing  mosquito 
larvae.  State  the  estimated  cost.  Mention  where  the 
money  is  coming  from.  Remind  the  readers  of  suc- 
cesses elsewhere.  The  editor  of  the  newspaper  should 
welcome  this  as  good  "  copy  "  ;  and  if  a  correspon- 
dence is  started  concerning  the  project,  so  much  the 
better. 

61 


62  PRELIMINARIES 

Many  sanitary  reforms  are  started  badly.  It  is 
common  to  find  health  officers  beginning  important 
health  reforms  with  a  long  proposal  containing  a  tire- 
some schedule  of  irritating  by-laws  to  be  passed  by 
the  town  council.  The  by-laws  are  bound  to  tread 
upon  the  toes  of  somebody.  Then  ensues  an  endless 
discussion.  Lastly,  the  object  of  the  proposed  by- 
laws is  forgotten  in  the  heat  of  party  strife.  Little 
can  be  done  by  such  means.  The  writer  has  wit- 
nessed a  comedy  in  which  a  bacteriologist  memo- 
rialised a  Committee,  consisting  largely  of  natives, 
demanding  £50  for  the  destruction  of  twenty  goats 
which  had  Malta  fever.  But  the  memorial  was  so 
full  of  "  terrible  technical  terms  "  that  the  proposal 
was  negatived  before  it  was  read.  It  was  not  under- 
stood. Malta  fever  continues  there  as  before. 

The  reduction  of  domestic  mosquitos  is  best  con- 
ducted without  petty  rules  and  regulations,  which 
only  irritate  householders  more  than  mosquitos,  and 
persecute  the  proprietors  of  property.  Afterwards, 
if  a  new  by-law  is  urgently  needed  it  can  be  brought 
forward  with  experience  to  back  it  up.  But  at  first 
hew  legislation  should  be  avoided.  Advertise  the 
nature  of  the  proposed  work,  and  state  emphatically 
that  it  is  going  to  be  done.  Have  confidence,  and 
then  do  it.  In  many  countries  the  sanitary  author- 
ity has  not  the  power,  without  endless  formality,  to 
force  his  way  into  houses  with  a  view  to  finding  out 
insanitary  conditions.  The  only  way  to  overcome 
this  difficulty  is  to  advertise  openly  that  it  is  the 
mosquitos  that  are  going  to  be  attacked,  and  not  the 


ADVERTISEMENT   ESSENTIAL  63 

tenants.  In  this  way  the  difficulty  will  be  speedily 
overcome.  The  inhabitants  of  a  town  will  give  way 
to  the  weekly  visit  of  the  sanitary  authority  if  they 
realise  that  they  are  to  be  rid  of  the  pest  of  mos- 
quitos — especially  if  they  are  not  asked  to  pay  for  it 
directly  ;  but  if  they  think  that  as  a  result  they  are 
going  to  be  haled  before  a  judge  and  bench,  cross- 
examined,  fined,  and  perhaps  impaled,  they  will,  very 
naturally,  object  and  oppose  the  proposition.  Here, 
then,  is  the  reason  for  the  advertisement.  Obtain 
the  assistance  and  co-operation  of  the  doctors  and 
the  goodwill  of  all  the  influential  residents,  and  then 
opposition  will  vanish. 

At  Port  Said  there  is  a  law  forbidding  all  Govern- 
ment servants  to  enter  any  house  under  any  circum- 
stances whatever ;  the  sanitary  authority  had  no 
power  at  all — he  could  not  venture  off  the  streets, 
he  could  do  nothing.  The  difficulty  was  overcome 
in  the  way  described.  The  mosquito  campaign  was 
advertised,  and  then  the  landlords  and  tenants  gave 
their  permission  to  the  men  of  the  mosquito  brigades 
to  enter  their  houses  whenever  they  liked  for  the 
purpose  of  reducing  the  objectionable  and  unpopular 
mosquitos.  As  a  result,  the  sanitary  authority  enters 
every  house  in  the  town  once  every  week  at  the 
request  of  the  inhabitants,  and  he  can  now  go  ahead 
with  sanitary  reforms.  The  result  is  well  known  ;  but 
it  may  be  stated  here  that  although  the  work  has 
gone  on  continuously  for  five  years,  there  has  not  been 
a  single  complaint  against  it,  although  the  law  men- 
tioned above  still  exists.  The  men  of  the  mosquito 


64  PRELIMINARIES 

brigades  enter  every  house  in  the  town  regularly 
every  week.  In  consequence,  cesspools  and  base- 
ments have  been  rebuilt,  houses  rendered  more  sani- 
tary, the  death-rate  has  fallen,  and  mosquitos  and 
fevers  practically  abolished  ;  and  there  has  been  no 
opposition.  But  no  sanitary  by-laws  have  been  en- 
forced— there  are  none  to  enforce.  Persuasion  must 
be  the  keynote.  Do  not  force,  but  persuade.  Port 
Said  contained  among  its  inhabitants  the  most  ignor- 
ant and  perhaps  the  lowest  form  of  humanity — both 
European  and  native — extant.  Yet  their  opposition 
and  prejudice  to  sanitary  matters  and  measures  were 
overcome  by  persuasion- — not  by  force.  We  could 
not  force — we  had  not  the  power.  There  are  no 
sanitary  laws  in  Egypt  worthy  of  the  name.  We 
were  forced  to  persuade. 

The  next  preliminary  is  to  engage  the  personnel 
of  the  mosquito  brigades.  The  foremen  must  be 
respectable  men ;  and  there  should  be  one  for  each 
gang  of  workmen.  It  is  better  to  begin  with  one  gang 
first,  consisting  of  a  foreman  and  three  or  four  men, 
and  to  confine  their  work  to  one  small  quarter  of  the 
town.  Then,  when  they  have  learned  the  work,  to 
extend  operations  with  another  gang,  and  so  on  until 
the  whole  town  is  being  completed  every  week,  and 
every  house  visited. 

Apply  to  some  local  labour  contractors  and  tell 
them  of  the  want.  Ask  them  to  recommend  a 
respectable  and  honest  man  for  the  post  of  "  mousti- 
quier,"  or  foreman.  Preference  should  be  given  to  a 
man  living  or  having  a  family  in  the  town  ;  one  who 


CHOOSING   EMPLOYEES  65 

is  known  in  the  place.  In  Egypt  a  local  Greek  or 
Syrian  was  generally  employed  ;  one  who  owned  a 
small  shop  or  house  for  his  family,  and  who  had  been 
a  resident  for  some  years.  Such  a  man  is  less 
to  become  dishonest.  Find  out  the  rate  of  p 
such  a  man.  At  Port  Said  the  foreman  of  a  mosquito 
brigade  is  paid  at  the  rate  of  £5  per  month.  The  rate 
of  pay  will  vary,  of  course,  in  different  countries. 
But  it  is  better  to  pay  a  little  more,  if  funds  will  per- 
mit, to  ensure  getting  a  good  man.  The  foreman 
should  give  up  the  whole  of  his  time  to  the  work.  He 
should  be  engaged  by  the  month  and  paid  monthly. 
His  services  should  be  permanent,  subject  to  his  good 
behaviour.  All  the  foremen,  no  matter  in  what  part 
of  the  town  they  work,  should  be  on  an  equality ; 
good  service  should  be  rewarded  by  an  increase  of  pay, 
but  for  punishment  it  should  be  liable  to  stoppage — 
the  greatest  penalty  being  dismissal. 

The  workmen  should  be  labourers  ;  natives  are 
generally  employed.  Their  honesty  is  the  most  im- 
portant factor.  They  should  also,  therefore,  be  re- 
spectable and  sober  men.  The  engagement  of  idlers 
and  loafers  should  be  avoided.  They  should  be  en- 
gaged on  daily  pay,  which  can  be  paid  to  them  weekly 
or  fortnightly  as  arranged  or  convenient,  so  that  any 
one  of  them  that  misbehaves  can  be  discharged  at  a 
day's  or  a  week's  notice.  Both  the  foremen  and  the 
workmen  will  have  opportunities  and  temptations  to 
be  dishonest,  and  there  must  be  the  means  of  dealing 
with  such  cases  summarily.  But  if  care  is  taken  to 
select  good  men  at  the  outset,  much  worry  and  trouble 

5 


66  PRELIMINARIES 

may  be  saved.  There  is  nothing  that  does  more 
harm  to  a  work  of  this  nature  than  the  personnel 
contracting  the  name  of  being  lazy  or  dishonest.  If 
it  is  possible,  it  is  better  to  pay  a  little  more  to  obtain 
honest  men,  and  thus  to  avoid  constant  accusations 
of  theft  or  charges  of  petty  pilfering  against  the  men 
forming  the  mosquito  brigades. 

The  foremen  and  the  men  should  not  be  frequently 
changed.  The  idea  is  that  they  should  become  known 
and  respected  in  the  town  by  the  householders  as  the 
men  that  prevent  mosquitos.  Every  one  should  know 
them,  and  who  they  are.  Therefore  engage  good 
men  and  keep  them.  They  will  be  required  to  work 
every  day  from  7  a.m.  until  5  p.m.,  except  Sundays, 
which  are  holidays  ;  but  should  mosquitos  reappear, 
they  will  be  required  to  work  overtime. 

The  oil  should  be  supplied  by  contract.  The 
amount  required  per  year  is  known.  This  amount 
should  be  advertised  for,  or  the  various  oil  merchants 
written  to  for  quotations.  Then  these  quotations 
may  be  considered  impartially  ;  that  one  adjudicated 
the  cheapest  may  be  accepted.  A  written  contract 
or  agreement  should  be  drawn  up  by  which  a  certain 
amount  of  oil — refined  and  crude — is  delivered  at  a 
particular  place  agreed  upon,  daily,  except  Sundays, 
during  the  year  at  a  regular  price.  It  is  better  to 
settle  one  place,  such  as  a  disinfecting  station,  where 
the  oil  can  be  delivered.  If  it  is  against  the  local 
statutes  to  store  the  petroleum  within  the  precincts 
of  the  town,  it  must  be  delivered  either  in  tubs  or  in 
barrels.  Provision  may  be  made  in  the  contract  for 


EXPERIENCES  67 

the  regular  return  of  such  tins,  tubs,  or  barrels,  and 
allowance  given  for  them  in  the  bills.  Or  such  barrels 
may  be  bought  outright,  and  used  over  and  over 
again.  Usually,  however,  oil  merchants  charge  for 
the  hire  of  the  tins,  and  deduct  the  price  of  the  hire 
if  they  are  returned  uninjured.  It  is  the  duty  of  the 
foremen  to  see  that  they  are  carefully  handled.  The 
amount  of  oil  required  per  day  should  be  supplied 
only  on  the  written  voucher  signed  by  the  head 
of  the  department  organising  the  campaign.  The 
vouchers  should  be  returned  with  the  monthly  ac- 
counts, and  they  serve  as  a  check  on  the  bills.  The 
foremen  should  give  a  receipt  every  day  to  the  oil 
purveyor,  stating  that  the  amount  received  is  as 
ordered,  and  that  its  condition  is  satisfactory — for 
sometimes  it  is  so  mixed  with  water  by  the  middleman 
that  it  is  useless  as  a  mosquito  larvicide.  The  oil — 
refined  and  crude — may  be  supplied  already  mixed 
by  the  purveyor,  or  it  may  be  mixed  by  the  men  of 
the  brigades  as  convenient  or  cheapest.  In  some 
countries  the  percentage  of  refined  oil  to  crude  oil  is 
found,  by  experiment  as  to  its  larvicide  properties, 
to  vary  considerably  according  to  the  temperature 
and  humidity  of  the  air  ;  then  allowance  must  be 
made.  If  the  oil  is  too  thin,  more  crude  petroleum 
must  be  added  ;  or  if  too  thick  to  spread  evenly,  more 
refined  oil  than  equal  parts  will  be  required. 

Each  mosquito  brigade  will  need  an  oil-barrel 
fitted  to  a  pair  of  wheels  with  hand  shafts  so  that  it 
may  be  pushed  through  the  streets  ;  horse  transport 
is  an  unnecessary  expense.  The  barrel,  which  may 


68  PRELIMINARIES 

be  made  of  iron,  as  it  is  more  durable  than  wood, 
should  be  capable  of  holding  sufficient  oil  for  the 
consumption  of  each  brigade  per  day.  It  should 
have  a  hole  at  the  top  and  a  brass  tap  at  one  end. 
Each  workman  should  be  given  a  bucket  and  a  tin 
one-litre  measure  ;  and  he  should  be  supplied  with  a 
bundle  of  cotton-waste  and  a  broomstick.  The  fore- 
man's equipment  consists  of  a  notebook  and  pencil. 
He  can  be  given  a  distinctive  uniform  if  it  is  thought 
desirable. 

With  these  preliminaries  accomplished  all  is 
ready  for  a  start,  which  need  not  be  delayed.  If 
there  is  a  large  ignorant  population  in  the  town,  the 
first  brigade  should  be  instructed  to  begin  operations 
in  the  residential  district  occupied  by  Europeans.  If 
it  is  successful  there,  the  natives  will  soon  begin  to 
ask  for  an  extension  to  their  quarter  also.  But  there 
should  be  no  delay  after  the  preliminaries  are  settled 
and  the  work  has  been  well  advertised. 

When  actually  starting  the  campaign  the  foremen 
and  workmen  should  be  shown  mosquito  larvae  and 
pupae  in  a  glass  of  water,  and  the  experiment  of  drop- 
ping  oil  on  to  its  surface  repeated  before  them. 
Then  empty  some  of  the  water  on  to  the  ground  and 
let  them  watch  the  mosquito  larvae  die  as  the  water 
dries.  This  is  to  teach  them  the  nature  of  their 
work. 


CHAPTER    VII 

THE    START 

ONE  Monday  morning  should  be  chosen,  and  the 
foreman  ordered  to  take  his  brigade  of  men  and 
his  oil-cart  to  a  corner  of  that  quarter  of  the  town 
decided  upon.  It  should  be  done  quietly,  or  a  crowd 
will  be  collected  as  a  result  of  the  advertisement.  He 
must  take  with  him  a  copy  of  the  survey  map  or  a 
sketch  of  the  quarter  in  which  he  works,  and  on  which 
the  houses  are  divided  up  into  equal  portions  for 
each  day.  He  must  place  the  oil-cart  in  a  shady 
place  in  the  street  or  avenue  where  the  work  is  to  be 
started. 

Taking  one  man  with  him  and  a  bucketful  of  oil, 
he  enters  the  garden  of  the  first  house,  and  asks  the 
servant  if  there  are  many  mosquitos  in  the  house. 
The  servant  goes  in  search  of  the  mistress  of  the 
establishment,  who  appears  and  demands  the  reason 
of  the  visit.  The  foreman  must  explain  his  presence. 
If  the  work  has  been  properly  advertised  the  mistress 
or  master  of  the  house  will  be  pleased  to  see  him. 
The  foreman  must  say  that  he  has  come  to  look  for 
and  to  destroy  mosquitos.  If  the  people  of  the  town 
have  been  already  warned  of  this  visit,  their  curiosity 

69 


70  THE    START 

will  overcome  any  opposition.  The  foreman  then  in- 
spects the  garden  or  compound.  He  must  look  for 
a  fountain,  and  examine  the  water  in  it.  If  there 
are  goldfish  present  he  will  find  no  mosquito  larvae 
there,  and  the  fountain  may  be  left  to  take  care  of 
itself.  Next,  he  looks  for  some  puddles  of  water  in 
the  garden.  If  there  are  any,  he  must  tell  the  servants 
that  such  are  dangerous  and  should  be  allowed  to 
dry  up.  If  there  are  mosquito  larvae  in  the  puddles, 
let  the  workman  put  a  few  drops  of  oil  on  to  the 
water  ;  or  he  may  be  directed  to  brush  out  the  water 
with  a  broom.  The  foreman  then  proceeds  to  ex- 
amine the  backyard.  Let  him  look  for  broken 
bottles,  jars,  or  buckets  containing  water.  These 
must  be  completely  emptied  out.  Any  washtubs  con- 
taining dirty  water  and  soapsuds  must  be  capsized. 
The  mis.tress  of  the  house  will  look  on  with  amuse- 
ment, but  her  amusement  will  turn  to  horror  when  the 
cesspool  is  opened,  and  myriads  of  mosquitos  fly  out 
of  it  accompanied  by  an  army  of  cockroaches.  The 
cesspools  of  houses  in  compactly  built  towns  are 
usually  situated  under  or  near  the  backyard,  and 
there  is  commonly  an  iron  lid  to  them  that  is  screwed 
down.  This  must  be  opened.  If  the  position  of  the 
cesspool  is  not  accurately  known,  it  can  usually  be 
found  by  examining  the  ventilation  pipes.  These 
pass  direct  from  the  cesspool  up  the  side  of  the  house. 
Or  the  soil-pipes  and  their  position  generally  indicate 
the  site  of  the  cesspool. 

The  workman  must  be  directed  to  pour  oil  into 
the  cesspool.      The  surface  extent  of  the  water  it 


A  house  cistern.    It  is  a  breeding-place  for 
domestic  mosquitos. 

(After  Boyce.) 


A  water-butt.     A  breeding-place  for  domestic  mosquitos. 

(After  Boyce.} 


[p.  71 


IN    EACH    HOUSE  71 

contains  can  generally  be  roughly  estimated  by  look- 
ing through  the  open  door.     One  litre  of  mixed  oil  to 
every  square  metre  of  water  surface  is  the  measure 
allowed  ;    it  need  not  be  exact.     The  oil  must  be 
poured  in  from  the  litre  measure,  and  then  the  water 
in  the  cesspool  well    stirred  with  the  broomstick  to 
ensure  that  the  oil  spreads  evenly.     If   the  cesspool 
cannot  be  found,  but  is  known  to  exist,  some  oil 
should  be  poured  into  each  water-closet  and  sink. 
This  will  pass  with  the  seal-water  into  the  cesspool, 
and  spread  over  its  surface  ;    but  this  method  is  not 
so  efficacious  as  actually  opening  the  cesspool  itself. 
The  householder  should  then  be  invited  to  see  that 
all  water  collections  in  the  house  are  emptied  on  that 
day  every  week  regularly.     All   flower  vases,  jugs, 
basins,  buckets,  saucers,  or  anything  that  contains 
water  must  be  dried  out. 

If  the  water  cisterns  on  the  roof  are  exposed  to 
the  hot  sun,  or  if  they  contain  only  filtered  water, 
there  will  be  no  mosquito  larvae  in  them  probably, 
and  they  may  then  be  ignored.  But  if  these  conditions 
are  not  present,  and  mosquitos  are  found  breeding  in 
house  cisterns  or  water  tanks,  it  is  better  to  cover 
them  with  a  fine-mesh  galvanised-iron  wire  net.  In 
some  towns  the  only  mosquitos  found  breeding  in 
such  cisterns  are  the  harmless  Theobaldia  spathipalpis, 
which  do  not  suck  blood.  (This  observation  applies 
to  the  Mediterranean  littoral  only.)  Turn  on  the  water 
in  the  bathroom  and  see  if  any  mosquito  larvae  or 
pupae  are  in  it,  and  act  accordingly.  Lastly,  warn 
the  householder  to  look  out  for  dirty  water  in  the 


72  THE    START 

kitchen,  and  to  have  it  emptied  out  every  Monday 
morning  by  the  time  the  brigade  arrives.  There 
should  be  an  axiom  published  broadcast  in  the  town  : 
"  No  Stagnant  Water." 

The  foreman  then  returns  to  the  street,  and  he 
writes  the  name  of  the  street,  the  number  or  name  of 
the  house,  the  name  of  the  householder,  the  total 
water  collections,  the  places  where  he  found  mosquito 
larvae,  the  amount  of  oil  used,  and  lastly  the  name 
of  the  workman  that  accompanied  him.  This  house 
must  always  be  appropriated  to  the  same  workman, 
and  he  must  be  responsible  for  the  mosquitos,  or  their 
absence,  in  it.  If  necessary,  the  workman's  name  can 
be  written  on  the  wall  of  the  house  so  that  there  can 
be  no  mistake. 

The  workman  is  then  directed  to  refill  his  bucket 
from  the  oil-cart  in  the  street,  and  to  repeat  the  same 
process  in  the  next  house.  In  the  meantime,  the 
foreman  takes  another  workman  into  another  house 
and  instructs  him  like  the  first,  and  so  on.  It  does 
not  take  a  long  time  to  teach  the  workmen.  At  the 
beginning  work  will  be  slow  ;  for  the  first  two  or  three 
weeks  the  men  will  not  be  able  to  accomplish  all  the 
houses  allotted  to  the  brigade  on  the  map.  But  as 
the  house-to-house  visit  becomes  familiar,  every  house 
in  the  district  apportioned  to  each  brigade  will  be 
visited  seriatim  every  week.  The  ultimate  object  is 
that  every  house  in  the  town  as  well  as  the  gardens 
will  be  visited  by  the  same  workman  at  the  same  hour 
of  the  same  day  every  week.  In  this  way  the  tenants 
will  know  when  to  expect  the  brigade,  and  they  can 


THE    BRIGADE    AT    WORK  73 

then  complain  to  the  foremen  if  the  work  is  not 
carried  out  regularly  or  properly. 

As  soon  as  one  brigade  is  in  full  working  order 
another  may  be  organised,  and  so  on  until  the  whole 
town  is  visited  regularly.  The  foremen  should  report 
to  their  chief  once  every  day,  and  inform  him  where 
they  find  mosquitos,  or  if  any  difficulties  have  been 
encountered.  They  can  also  bring  samples  of  mosquito 
larvae  found,  and  the  insects  may  be  classified.  But 
their  time  will  be  fully  occupied  at  the  outset  in 
finding  out  the  breeding-places  of  mosquitos,  and  they 
must  be  urged  to  do  their  work  thoroughly.  Both 
the  foremen  and  workmen  are  liable  to  become  lazy 
after  a  time,  for  their  work  is  monotonous  ;  native 
workmen  require  constant  exhortation.  As  time  goes 
on,  however,  and  the  men  learn  their  work  thoroughly, 
their  duties  will  become  lighter.  They  will  soon 
learn  where  the  common  breeding-places  are,  and 
find  out  the  geography  of  each  house  and  its  com- 
pound. At  the  present  time,  at  Port  Said  each 
brigade  deals  with  nearly  6,000  houses  every  week  ; 
but  many  of  these  are  houses  or  huts  or  small  shops 
that  require  but  little  supervision. 

Suppose  a  householder  refuses  admission  to  a 
workman,  giving  some  lame  excuse  for  his  action. 
The  workman  must  immediately  report  the  fact  to 
the  foreman.  The  foreman  should  then  go  and  speak 
to  the  householder  and  try  to  persuade  him.  If  this 
fails,  let  the  brigade  leave  the  house  alone  for  a  week. 
No  attempt  must  be  made  to  force  an  entrance. 
Police  interference  must  be  avoided  always.  Leave 


74  THE    START 

the  house  to  take  care  of  its  own  mosquitos  for  a  time. 
The  wayward  householder  will  soon  change  his  atti- 
tude. Mosquitos  will  continue  to  worry  him  and  his 
children,  and  then  his  neighbours  will  complain. 
This  will  soon  bring  him  to  his  senses.  Householders 
will  sometimes  bring  forward  the  most  extraordinary 
excuses  to  justify  their  action  in  refusing  admission 
to  the  moustiquiers  and  the  workmen  into  the  back- 
yards of  their  houses.  It  is  because  they  are  frightened 
at  the  visit  of  the  sanitary  authority,  and  fear  pains 
and  penalties  at  the  hands  of  the  law.  One  man 
objected  at  Port  Said  because  he  preferred  the  bites 
of  mosquitos  to  the  smell  of  petroleum  once  a  week  ; 
he  owned  a  most  insanitary  fried-fish  shop.  Another 
said  that  he  liked  mosquitos  ;  the  pleasant  buzzing 
noise  the  insects  make  amused  his  children — they 
were  always  ill,  and  had  plenty  of  opportunities  of 
listening  to  the  music.  The  man's  house  was  flooded 
with  sewage,  and  he  did  not  want  to  go  to  the  expense 
of  emptying  his  cellars  and  cesspool,  which  had  burst. 
A  third  said  that  mosquitos  were  put  into  the  world 
by  the  Deity  to  punish  recalcitrant  human  beings, 
and  that  it  would  be  a  sin  to  try  to  reduce  them  ;  he 
was  a  very  devout  man  until  his  next  attack  of  fever, 
when  his  devotion  suddenly  disappeared.  A  native 
said  that  the  British  official  was  poisoning  the  water 
in  his  cesspool — perfidious  Albion  again ! 

It  is  better  to  leave  such  people  alone  until  they 
realise  the  stupidity  of  their  action.  If  they  remain 
obdurate,  a  little  tact,  as  will  be  described  later,  will 
generally  overcome  their  prejudices.  Complaints  will 


DISCRETION  75 

arise  that  the  workmen  drop  black  oil  about  the 
houses,  or  on  the  premises  ;  they  must  be  exhorted  to 
be  careful  of  such  complaints.  Or  the  lids  of  the  cess- 
pools may  not  have  been  properly  screwed  down,  or 
the  servants  have  been  insulted,  etc. ;  there  are  fre- 
quently such  grievances  when  the  campaign  first 
starts.  Such  complaints  must  be  inquired  into,  and 
the  foremen  should  be  held  responsible.  But  such 
opposition  wears  off  as  the  men  learn  their  work  and 
the  mosquitos  disappear.  In  laundries  the  masters 
sometimes  grumble  at  the  tubs  being  emptied.  The 
soapy  water  is  used  over  and  over  again,  and  if  they 
are  emptied  out  when  most  required,  it  gives  extra 
trouble.  Arrangements  must  be  made  to  suit  the 
convenience  of  such  trades,  and  the  masters  can  be 
asked  to  dry  out  their  tubs  on  Saturday  nights, 
when  the  work  of  the  laundry  is  finished  for  the 
week.  These  difficulties  can  always  be  overcome  by 
a  little  patience.  Discretion  must  be  employed. 
There  is  no  need  to  pour  oil  into  tanners'  vats,  for 
example  ;  nor  to  empty  wine  and  vinegar  jars  ;  nor 
to  oil  gas-engine  circulating  cisterns — the  water  in 
them  is  too  hot  for  mosquito  larvae,  and  the  oil  is 
liable  to  choke  the  engine. 

If  there  is  a  large  separate  native  location  it  should 
not  be  neglected.  But  in  some  countries  the  natives 
may  give  trouble.  This  is  often  due  to  political 
agitation.  Sanitary  measures  among  natives  in  India, 
Egypt,  and  in  other  countries  have  given,  and  may 
again  give,  rise  to  riots.  The  best  way  to  avoid  this 
is  to  copy  the  methods  employed  on  the  Suez  Canal. 


76  THE    START 

At  Port  Said,  when  plague  broke  out  in  1900, 
some  small  "  incidents  "  occurred  when  the  Sanitary 
Department  began  soaking  the  houses  of  the  native 
quarter  in  a  solution  of  perchloride  of  mercury.  I 
think  the  natives  were  to  be  sympathised  with,  for 
these  measures  did  no  good,  cost  a  great  deal,  and 
entailed  much  discomfort.  The  natives  also  objected 
to  the  plague  subjects  being  forcibly  segregated  in 
whole  families.  They  became  troublesome,  and  the 
police  were  obliged  to  interfere  to  protect  the  doctors. 
Thus  people  were  frightened  at  the  name  of  sanitation. 
Consequently,  when  the  anti-mosquito  campaign  was 
suggested,  they  feared  a  repetition  of  the  trouble, 
and  an  outcry  arose.  It  was  easily  overcome,  how- 
ever, by  confining  the  work  of  the  first  brigade  to  the 
houses  of  the  better-educated  European  residents. 
The  mosquitos  disappeared  from  these  houses,  not- 
withstanding the  close  proximity  of  the  native 
quarter,  which  is  only  separated  from  the  European 
part  of  the  town  by  the  width  of  one  street,  and  then 
the  natives  themselves  began  to  complain  :  "  Why 
are  we  left  out  ?  Is  this  the  British  occupation  of 
Egypt  ?  "  Six  years  before  they  had  thrown  boiling 
oil  over  the  doctors'  heads. 

The  answer  was  simple.  Another  brigade  was  at 
once  organised  and  the  native  quarter  was  cleared  of 
its  mosquitos  too,  the  natives  themselves  assisting  in 
the  work.  Now  Port  Said  is  wholly  under  anti- 
mosquito  rule — native  and  European  quarters  alike. 

The  work  will  soon  begin  to  be  talked  about ;  this 
should  be  encouraged.  Let  everybody  know  of  it,  so 


ORGANISATION  77 

that  the  townsfolk  can  discuss  it  on  its  merits.  The 
mosquito  brigades  are  entering  every  house  in  the 
town  at  the  same  hour  of  the  same  day  every  week. 
They  are  examining  regularly  all  shops  and  houses, 
inspecting  the  cesspools,  wash-houses,  factories, 
water-closets,  basements,  gardens,  compounds,  tan- 
neries, triperies,  slaughter-houses,  and  are  dealing 
with  insanitary  places  as  they  find  them.  What 
better  sanitary  organisation  can  there  be  than  this  ? 
The  health  officer,  or  the  municipal  council,  or  ad- 
ministration, whatever  it  may  be,  is  receiving  regular 
reports  concerning  the  condition  of  the  town.  It  is, 
then,  prepared  to  deal  with  disease-producing  centres  ; 
it  is  now  in  a  position  to  know  of  them — before  it 
was  not.  The  time  is  ripe  for  progress.  " 


CHAPTER    VIII 

PROGRESS 

THE  ^fgaustiguiers^}  or  foremen,  will  soon  begin  to 
report  that  they  are  finding  mosquitos  breeding  in 
peculiar  places,  and  that  they  are  puzzled  to  know 
how  to  deal  with  them.  Perhaps  one  has  discovered 
that  a  certain  house  is  mosquito-infested  because  the 
cesspool  has  burst,  and  the  sewage  is  leaking  out  and 
has  swamped  the  cellars  of  that  and  neighbouring 
houses.  He  has  discovered  that  it  is  a  waste  of  oil 
to  deal  with  this  large  expanse  of  water,  but  that 
the  mosquitos  are  breeding  there  in  myriads.  If 
there  is  any  sanitary  law  in  the  land  this  state  of 
affairs  should  be  easily  remedied.  But  in  many 
countries  where  mosquitos  abound  there  is  little 
sanitary  law,  or  if  there  is  any,  it  is  so  drawn  up  that 
it  cannot  be  enforced. 

The  landlord  should  be  approached.  If  he  can 
be  persuaded  to  repair  the  cesspool,  all  well  and 
good.  If  he  refuses  he  must  be  forced  to  do  so.  But 
suppose,  as  in  Egypt,  there  is  no  law  to  force  him. 
Then  he  must  be  talked  to  seriously.  If  this  has  no 
effect,  deal  with  him  "  tactfully,"  as  the  diplomatists 
describe  it.  Induce  his  tenants  to  write  to  him  and 

78 


DIPLOMACY  79 

complain  of  the  smell,  to  threaten  to  leave  his  prem- 
ises ;    and  give  them  a  certificate  saying  the  place  is 
insanitary.     The  immediate  result  will  be  that  the 
landlord    will    refuse    admission    to    the    mosquito 
brigade.     Then  the  neighbours  will  complain  of  mos- 
quitos.     If  this  is  unfruitful  of  results,  it  is  best  to 
approach    his   employer — if   he   has    one.     There   is 
certain  to  be  some  one  in  the  town  with  whom  he  is 
intimately    connected.     Perhaps    the   landlord    is    a 
clerk  in  a  shipping  office.     Interview  the  head  of  the 
firm  and  ask  him  to  admonish  his  refractory  employe. 
The  cesspool  will  be  repaired  rapidly.      A  Maltese 
ship-chandler  had  a  most  insanitary  house  which  he 
had  let  in  flats.     The  tenants  were  always  ill  with 
fever.     He   was   careful   to   live   elsewhere   himself. 
The  Health  Department  remonstrated,   cajoled,  im- 
plored, without  avail.     He  said  that  the  Maltese  were 
a  down-trodden  race  persecuted  by  England,  and  he 
would  not  do  anything.     Suddenly  a  ship  came  into 
port,  and  the  captain  refused  his  goods,  taking  those 
of  his  rival.     This  was  repeated.     He  complained  of 
unfairness  to  the  shipping  agent,  and  was  informed 
that   "  We  are  not  so  unfair  to   you  as   you  are   to 
your  sick  tenants."     The  result  was  that  the  house 
was  repaired,  cleaned,  and  partly  rebuilt.     There  were 
several  other  instances  of  a  similar  nature.     A  clerk 
in  a  French  company  let  part  of  his  house  to  a  poor 
family,    all   of   whom   suffered   from   the   results   of 
insanitation.     He  had  repeatedly  refused  admission 
to  the   mosquito  brigade,   and   domestic   mosquitos 
continued  to  breed  in  the  wash-tubs  on  the  roof.     We 


80  PROGRESS 

applied  to  the  director  of  the  company.  The  next 
time  the  clerk  was  ill  and  obliged  to  absent  him- 
self from  the  office  he  was  informed  that  the  company 
disliked  sick  employes,  and  it  would  be  to  his  ad- 
vantage if  he  put  his  house  in  order.  The  mosquito 
brigade  was  at  once  sent  for  by  the  clerk.  M. 
Leonidas  was  a  Greek,  a  great  man,  for  he  was  a  Con- 
sul. He  owned  the  only  meat  market  in  the  town. 
This  meat  market  was  in  a  foul  state,  for  the  base- 
ment was  flooded  with  sewage  to  a  depth  of  four  feet. 
He  refused  to  make  repairs  and  could  not  be  forced 
to  do  so — he  was  a  Consul.  Eventually  he  was  con- 
strained to  rebuild  the  meat  market  in  consequence 
of  representations  to  the  Government  which  he  repre- 
sented ;  for  the  tenants  of  the  market  joined  together 
and  approached  the  Ambassador. 

But  it  is  rare  that  the  needs  of  public  health  re- 
quire such  lengths  of  diplomacy.  In  the  majority  of 
instances  a  little  persuasion  will  accomplish  all  that 
is  wanted  provided  that  the  landlords  have  the 
means.  A  native,  named  Mohammed,  came  to  the 
office  and  salaamed.  He  said,  in  high-flown  Arabic, 
that  the  foreman  of  the  mosquito  brigade  had  asked 
him  to  fill  up  a  well  which  he  had  sunk  in  the  floor 
of  his  house  ;  he  could  not  afford  to  make  a  proper 
cesspool.  In  consequence  the  whole  of  the  base- 
ment of  the  house  was  flooded  with  sewage.  He  was 
willing  to  fill  up  this  well,  but  he  could  not  afford  to 
pay  for  the  cartage  of  sand  from  the  seashore  to  the 
house,  and  a  great  deal  of  sand  would  be  required.  A 
telephone  message  to  the  superintendent  of  police 


'  TACT  »  81 

showed  that  Mohammed  was  indeed  a  very  poor  man, 
and  had  a  large  family  to  support.  His  house  was 
rat-infested,  and  one  of  his  sons  had  died  of  plague 
the  year  before.  Therefore  the  necessary  sand  was 
conveyed  to  his  door  at  the  expense  of  the  mosquito 
fund,  and  then  he  and  his  family  borrowed  shovels 
and  filled  up  the  cellars.  There  has  been  no  plague 
there  since,  and  his  mosquitos  have  disappeared. 

The  moustiquiers  will  also  discover  many  other 
sanitary  defects  in  the  town  of  a  similar  nature  to 
these.  Their  regular  visit  will  disclose  many  matters 
that  will  astonish  the  sanitary  inspectors.  They  will 
report  the  presence  of  laundries  and  wash-houses, 
clothes-ironing  shops,  bakeries,  skin-curing  depots, 
leaking  and  unsafe  steam  engines  and  boilers,  cafes 
and  dirty  restaurants,  and  many  other  insanitary 
trade  depots  that  exist  unknown  to  the  town  council 
or  ever  licensed  by  it.  Such  must  be  dealt  with 
gently,  and  the  owners  invited  to  put  their  establish- 
ments in  order.  Choked  rain-water  gutters  and  eaves, 
drains,  and  old  sewers  will  be  found.  Blocked  canal- 
ends  and  pools  of  stagnant  water  will  be  discovered 
in  the  most  unlikely  places  ;  and  wells  sunk  into 
the  subsoil  water  to  save  the  water-rate  will  also  be 
unearthed.  Holes  in  trees  containing  rain-water, 
garden  irrigation  reservoirs,  railway  borrow-pits,  infil- 
tration water  collections,  ornamental  ponds,  steam- 
launch  water  tanks,  barge  bilge-water,  and  many 
other  mosquito-breeding  foci  will  have  to  be  dealt 
with  each  on  its  own  merits.  The  foremen  and  the 
workmen  will  soon  find  them  out  and  report  on  their 


82  PROGRESS 

existence.  These  seldom  give  rise  to  difficulty,  and 
only  require  a  dogged  perseverance  in  discovering  and 
dealing  with  them. 

But  sooner  or  later  some  one  will  become  offended. 
Perhaps  a  landlord  has  been  unduly  irritated  because 
the  mosquito  brigade  has  discovered  some  insanitary 
condition  in  his  house  that  the  tenants  have  also  dis- 
covered, and  they  are  grumbling ;  perhaps  he  has 
been  obliged  to  spend  more  money  on  repairs  than  he 
anticipated  in  his  annual  estimate  of  pecuniary 
dividend.  He  has  resented  this,  and  seeks  revenge. 
He  may  spread  reports  about  that  the  mosquito  work 
is  a  fad,  is  unsuccessful  because  there  are  still  mos- 
quitos  in  the  town,  that  all  the  tenants  still  have 
fever,  that  "  it's  all  nonsense  "  and  a  waste  of  money. 
He  may  write  to  the  newspaper,  or  bring  up  a  reso- 
lution at  the  local  council  board.  Let  him  ;  for  if 
the  work  has  been  begun  and  carried  out  properly,  he 
will  find  himself  in  the  minority — he  will  be  laughed 
at.  That  is  all  the  thanks  he  will  get  for  his  pains. 
If  others  are  satisfied,  well  and  good  ;  and  they  will 
be  satisfied  if  sincere  attempts  have  been  made  to  get 
rid  of  mosquitos.  Every  one  will  know  that  the  man 
is  a  landlord  with  a  grievance,  and  will  regard  him 
accordingly. 

Accusations  of  theft  against  the  foremen  and  the 
workmen  may  be  made.  These  must  be  inquired 
into  carefully  and  impartially.  Petty  pilfering  is 
quite  possible,  for  they  have  the  opportunities  for 
doing  it.  Examine  each  case.  If  there  is  reason  to 
believe  that  the  charge  is  sound,  punish  accordingly. 


DISCIPLINE  83 

The  foremen  may  be  discharged  at  a  month's  notice, 
and  the  workmen  are  on  daily  wages.  But  do  not 
punish  unjustly,  or  good  men  will  be  difficult  to  ob- 
tain. If  there  is  a  clear  case,  make  an  example  and 
be  firm. 

Should  a  district  be  cleared  of  mosquitos,  and  then 
the  insects  return  suddenly,  the  foreman  should  be 
made  to  inspect  the  neighbourhood  carefully.  If  he 
finds  larvae  in  a  place  that  should  have  been  dealt 
with  by  one  of  the  workmen  in  his  weekly  visit,  and 
the  man  has  neglected  to  do  so,  he  should  be  warned. 
The  workman's  name  is  on  the  door  of  the  house  and 
in  the  foreman's  notebook,  and  he  must  be  held 
responsible.  If  the  mosquitos  recur  a  second  time 
the  workman's  pay  may  be  stopped  for  a  day  or  two, 
and  if  the  offence  is  repeated  he  may  be  discharged. 

Sometimes  a  foreman  will  report  that  in  a  certain 
house  mosquitos  persist  in  great  numbers,  and  that 
he  cannot  find  the  larvae.  In  this  case  make  the 
whole  brigade  search  in  the  garden  and  on  the 
premises  until  the  larvae  are  found.  If  they  are  in 
large  numbers  in  one  house,  and  by  examining  the 
mosquito  curtains  in  the  bedrooms  many  male  as 
well  as  female  mosquitos  are  found  there,  then  it  is 
certain  that  the  breeding-place  is  not  very  far  off. 
Examine  the  basement  and  the  cesspools.  Perhaps 
there  is  a  buried  cesspool  or  an  unused  water-closet, 
and  the  mosquitos  are  laying  their  eggs  in  the  seal- 
water.  If  the  search  is  thorough,  the  larvae  are  sure 
to  be  found. 

Should  mosquitos  return  in  a  district  that  has 


84  PROGRESS 

already  been  cleared,  and  the  foreman  reports  that 
he  cannot  find  their  breeding-place,  insist  that  the 
brigade  works  after  working  hours,  or  on  the  following 
Sunday,  until  the  larvae  are  found  ;  this  will  make 
them  more  careful.  If  this  is  done,  the  mosquito 
breeding-place  is  always  forthcoming.  Complaints 
may  arise  that  a  house  has  not  been  visited  by  the 
brigade  for  a  month,  and  that  the  foreman  has  been 
seen  idling  away  his  time  in  a  cafe.  Find  out  if  the 
accusation  is  correct.  A  few  inquiries  will  soon  settle 
the  matter.  If  correct,  punish  heavily,  and  the 
offence  will  not  be  repeated.  Make  the  men  work 
overtime,  or  cut  their  pay.  But  one  must  be  fair 
and  just — then  the  men  will  work  well. 

It  may  be  found  that  mosquitos  are  breeding  in 
places  that  are  difficult  to  deal  with  on  account  of 
the  expense.  Such  places  are  large  borrow-pits,  in- 
filtration water  collections,  birkets,  urban  marshes. 
As  already  pointed  out,  the  drainage  or  the  reclaiming 
of  such  places  really  comes  under  the  heading  of  major 
sanitary  works,  and  should  have  been  noted  as  such 
when  making  the  estimate  of  the  cost.  Such  major 
sanitary  works  should  be  undertaken  by  the  munici- 
pality or  town  council  as  its  duty  ;  it  should  not  be 
left  to  the  enterprise  of  some  individual  department 
— certainly  not  put  to  the  account  of  a  mosquito 
campaign.  The  reclaiming  of  a  ditch  in  the  centre 
of  a  town  should  not  be  charged  to  the  credit  of  the 
Health  Department  merely  because  it  is  insanitary 
or  because  it  smells.  These  are  general  municipal 
measures.  Frequently  one  sees  such  matters  forgotten. 


A  borrow-pit  in  which  domestic  mosquitos  breed. 


A  sewage-flooded  backyard  breeding  domestic  mosquito 


[p.  85 


DIFFICULTIES  85 

I  have  witnessed  a  Government  pass  a  proposal  for 
an  expensive  pier  or  an  opera  house,  disregarding 
the  fact  that  the  death-rate  in  the  town  was  40 
per  1,000. 

The    filling    up    of    borrow-pits    and    infiltration 
water  collections  is  often  an  expensive  matter.     In 
Egypt,  the  cultivated  area  is  restricted  to  the  valley 
and  the  delta  of  the  Nile.     And  as  there  is  no  im- 
permeable stratum  of  soil,  the  height  of   the  subsoil 
water   varies   with   the   level   of   the   river.     Every 
autumn  the  level  of  the  Nile  rises  owing  to  the  flood 
produced  by  the  monsoon  rains  in  Equatorial  Africa, 
and  consequently  the  level  of  the  subsoil  water  rises 
too.     There  are  throughout  Egypt,  in  the  cultivated 
area  and  in  the  towns,  many  natural  and  artificial 
hollows  and  depressions  in  the  land  surface,  called 
birkets.     When    the    Nile    has    reached    a    sufficient 
height  the    subsoil  water    infiltrates  from  beneath, 
and  the  birkets  become  pools  of  fresh  water.     The 
numbers  of  these  pools  and  their  extent  varies  with 
the  maximum  height  of  the  river  at  its  annual  flood, 
but  the  water  often  remains  in  them  for  some  weeks 
after  the  river  has  begun  to  fall  again.     These  pools 
are  suitable  breeding-places  for  all   species  of  mos- 
quitos  indigenous  to  Egypt,  and  the  insects  swarm. 
In  the  towns  and  villages  these  birkets  become  open 
cesspools,  and  the  smell  from  them    is  terrible.     In 
Cairo,  during  the  annual  flood,  the  Nile  water  wells 
up  into  the  basements  and  cellars,  and  bursts  the  cess- 
pools, and  the  whole  town  is  converted  into  one  large 
sewage  swamp  in  the  high- flood  years — the  years  of 


86  PROGRESS 

the  "  fat  kine."  At  Port  Said,  the  sea  water  is  only 
one  metre  below  the  road  level,  and  there  too  the 
basements  were  flooded  frequently  with  a  mixture  of 
sewage  from  the  burst  cesspools  and  subsoil  water. 
Such  basements  were  filled  up  with  sand  from  the 
seashore  by  the  landlords,  who  were  persuaded  to  do 
it  at  their  own  expense  ;  but  the  sand  was  free,  and 
the  carriage  cheap.  In  Cairo,  on  the  other  hand,  the 
birkets  are  for  the  most  part  owned  by  the  Govern- 
ment, and  nothing  would  induce  the  Adminis- 
tration to  spend  money  for  the  purpose  of  reclaiming 
its  own  property.  In  Cairo,  the  filling-up  process,  so 
urgently  desired,  is  an  expensive  operation.  The 
common  price  charged  there  by  local  contractors  is 
Is.  2d.  per  cubic  metre,  including  the  cost  of  material, 
and  great  care  must  be  exercised,  or  new  birkets  will 
be  formed  by  the  borrow-pits  made  slyly  by  the  con- 
tractors— the  earth  must  be  obtained  from  some- 
where, as  street  sweepings  are  inadmissible  from  a 
health  standpoint.  Such  examples  as  these  are  set 
down  here  in  order  to  show  that  major  sanitary  works 
are  invariably  expensive,  and  that  the  reclaiming  of 
swamps  in  the  middle  of  large  towns  may  cost  much 
money,  even  when  the  water  comes  from  below, 
instead  of  from  above  as  rain. 

In  Port  Said  we  had  to  face  another  difficulty. 
Our  foremen  were  obliged  to  understand  and  to  speak 
six  different  languages.  The  town  contains  the  riff- 
raff of  all  the  nations  of  Europe  as  well  as  native 
Egyptians,  Syrians,  Indians,  and  others,  including 
Arabs  and  Bedawins.  All  these  people  are  under  the 


DIFFICULTIES    OVERCOME  87 

control  of  their  own  consuls  only,  and  the  sanitary 
authority  had  no  power.  Each  colony  is  self-con- 
tained, and  will  brook  no  interference  from  officials 
of  the  Egyptian  Government.  The  consuls  were 
often  haughty  personages  of  their  respective  diplo- 
matic corps,  and  it  was  frequently  found  a  hopeless 
undertaking  to  appeal  to  them  for  help,  though  some 
of  them  assisted  in  every  way.  We  were  forced  to 
employ  every  ingenuity  to  gain  our  object — public 
health.  It  is  to  be  hoped  that  others  will  not  meet 
with  these  unnecessary  difficulties,  but  they  are  set 
down  here  from  the  store-book  of  experience  so  that 
he  who  runs  may  read,  overcome,  or  steer  clear  of 
them.  Perhaps  in  the  place  of  the  difficulties  en- 
countered in  Egypt  others  will  arise  elsewhere,  and 
they  will  have  to  be  surmounted  in  a  like  manner  ; 
they  can  be  surmounted,  that  is  the  chief  thing.  If 
there  are  laws  that  will  assist  in  the  prohibition  of 
stagnant  water,  they  may  be  enforced  if  necessary. 
But  where  persuasion  will  obtain  the  same  result,  it 
should  be  employed  for  preference-  Popular  admin- 
istration does  more  for  the  community  than  despot- 
ism, and  it  is  more  lasting. 


CHAPTER    IX 

MOSQUITO    REDUCTION 

THE  mosquito  at  last  had  drunk  her  fill.     She  had 

•••*-"• — >..-v — —     &       *"^-^-^v^->-^ —        O*         «-*\-*X~ •&    ~'v — •*^-* — 

been  born  three  days  before  in  a  neighbouring  cess- 
pool. The  water  there  was  warm,  and  her  larval 
life,  from  egg  to  perfect  insect,  had  only  occupied 
about  fifteen  days.  On  emerging  from  the  water  she 
had  flown  about  in  the  foul  air  of  the  cesspool  for 
twenty-four  hours,  and  had  fed  on  the  floating  ex- 
crement. Then  she  had  consorted  with  a  male  of  her 
species — one  that  had  probably  arisen  from  the  same 
egg-raft  as  herself  ;  he  was  in  fact  her  brother.  Her 
spermathecae  were,  in  consequence,  full  of  sperma- 
tozoa, and  this  had  made  her  crave  for  a  more 
strengthening  diet  than  anything  the  cesspool  could 
give  her.  For  hours  she  had  striven  to  find  an  exit 
from  that  environment  without  success.  But  at 
length  she  had  found  her  way  with  a  swarm  of  others 
through  some  chink  into  the  adjoining  cellar,  and 
had  flown  up  the  stone  stairs  to  the  kitchen  on  the 
ground  floor.  It  was  the  evening  when  she  emerged 
into  the  society  of  human  beings,  and  the  air  was  still 
and  the  heat  overpowering.  The  long  flight  had  been 
accomplished  by  easy  stages,  for  she  was  famished  for 
blood,  and  had  been  obliged  to  rest  in  dark  corners. 

88 


THE    MOSQUITO'S    ROMANCE  89 

She  had  flown  to  some  clothes  that  were  hanging 
behind  the  door  and  had  rested  again. 

After  a  short  time  hunger  again  manifested  itself, 
so  she  tried  to  clean  her  proboscis  with  her  forelegs, 
but  it  only  made  them  sticky  and  uncomfortable. 
She  then  tried  to  thrust  the  end  of  the  proboscis  into 
the  cloth,  but  this  was  only  partially  successful,  and 
the  cotton  hurt  her  bristles.  She  flew  out  of  the 
kitchen,  which  was  deserted,  for  the  native  servants 
were  cackling  to  each  other  on  the  stoep,  and  she  at 
length  had  found  her  way  into  a  bedroom  where 
there  was  a  man  lying  ill  on  a  bed.  He  had  pushed 
the  mosquito  net  aside  to  get  more  air,  and  then  had 
fallen  asleep.  The  room  was  almost  dark.  She 
settled  at  once  on  the  mosquito  net,  waving  her  hind- 
legs  in  an  expectant  way.  The  thoughts  of  a  meal 
made  her  feel  a  pleasurable  excitement,  but  she  also 
felt,  instinctively,  the  need  for  caution. 

The  man's  hand  lay  exposed  on  the  coverlet,  so 
she  hopped  down  and  alighted  very  softly  on  to  the 
back  of  his  fingers.  Again  she  rubbed  her  proboscis, 
and  then  very  gently  attempted  to  thrust  it  through 
the  skin,  which  was  hot  and  pungent  with  fever ;  the 
sleeper  was  sweating  profusely.  But  the  skin  here 
was  hard,  and  she  could  not  pierce  it.  She  changed 
her  position  slightly  and  tried  another  spot,  where 
at  the  bottom  of  a  tiny  fold  between  the  palm  and 
the  little  finger  she  could  gain  an  entrance.  Imme- 
diately the  point  of  her  proboscis  entered  the  cuticle 
her  saliva  began  to  flow  into  the  skin,  and  before  she 
could  pierce  any  small  vein  the  sleeper  moved  his 


90  MOSQUITO   REDUCTION 

hand.  But  she  was  ready  for  this,  and  quickly  flew 
up  to  the  gathered  mosquito  curtain  above.  Soon 
all  was  quiet,  and  after  a  moment's  rest  she 
again  determined  to  venture  for  her  food.  She 
moved  down  gently  as  before  and  attacked  the  man's 
lip.  Here  she  obtained  a  few  minute  drops  of  blood, 
but  again  the  sleeper  moved,  and  she  was  obliged 
once  more  to  seek  her  refuge. 

The  frugal  meal  she  had  obtained  had  only 
whetted  her  appetite  for  more,  and  a  third  time  she 
returned  to  satisfy  her  lust.  This  time  she  ap- 
proached the  sleeper's  ear,  but  the  buzzing  her  wings 
made  woke  him,  for  he  suddenly  sat  up  in  bed 
with  an  oath,  waved  his  arms  about  his  head, 
and  then  set  himself  to  scratching  his  lip.  The  wind 
and  disturbance  he  made  with  his  arms  caused  the 
mosquito  to  fly  away  to  a  far  corner  of  the  room,  and 
contemplate  with  quaking  thoughts  the  difficulties  of 
obtaining  the  necessaries  of  life.  In  the  meantime 
the  sleeper  pulled  down  his  mosquito  curtain  and 
tucked  it  in  under  the  mattress.  She  tried  again  to 
approach  him,  but  he  had  hidden  himself  behind  an 
impregnable  fortress  of  muslin.  So  she  stood  on  the 
perpendicular  part  of  the  curtain  and  waited  as  the 
evening  closed  in. 

Suddenly  a  bat  flew  in  through  the  open  window, 
and  swooped  about  the  room,  attracted  by  the  small 
midges  that  were  disporting  themselves  in  a  shaft  of 
light  thrown  by  a  street  lamp  outside.  The  bat  did 
not  see  her,  but  its  presence  terrified  her  as  its  wings 
flapped  past  the  mosquito  net. 


THE   MOSQUITO'S   COMEDY  91 

At  last  her  hopes  of  renewing  her  meal  were  again 
raised  when  the  bedroom  door  opened  and  a  native 
servant  entered  carrying  a  tray.  She  at  once  settled 
on  his  clothes  near  his  bare  neck,  and  was  carried  by 
him  into  the  passage  of  the  house.  He  moved  so 
quickly,  however,  that  she  was  obliged  to  leave  him, 
and  entered  the  open  door  of  another  room.  Here 
there  was  a  child  asleep  in  a  cot  which  was  covered 
by  a  long  mosquito  curtain.  On  this  she  alighted, 
and  again  waited.  Presently  the  infant's  arm  was 
thrust  against  the  net,  and  then  she  was  able  to 
satisfy  her  appetite  from  its  blood.  But  on  this  oc- 
casion the  child  moved,  and  she  took  refuge  under  the 
bed,  as  she  realised  that  this  was  the  safest  place 
from  her  natural  enemies.  When  on  the  child's  net 
she  noticed  that  there  were  a  score  or  so  of  mosquitos 
like  herself,  with  their  bodies  distended  with  blood. 
But  there  were  only  two  males  among  them,  and  they 
both  belonged  to  an  alien  species,  and  they  had  not 
fed  on  the  child.  What  had  become  of  the  swarms 
of  males  that  she  had  left  in  the  cesspool  ?  She 
wondered  why  it  was  only  her  sex  that  required 
blood.  Why  had  she  to  risk  her  life  for  food  while 
her  husband  and  brothers  remained  contentedly  in 
their  home,  the  cesspool  ?  But  she  had  had  a  good 
meal  at  last,  and  it  was  making  her  drowsy.  Her 
body  was  distended,  and  it  sagged  downwards  with 
its  weight ;  this  tired  her  legs,  so  she  crawled 
up  the  net  to  a  place  where  a  fold  made  it  more 
horizontal,  and  she  could  get  a  hold  with  her  claws ; 
then  she  slept. 


92  MOSQUITO    REDUCTION 

That  night  and  all  the  next  day  she  slept  and 
digested  her  meal.  In  the  evening  she  felt  hungry 
again,  but  it  was  early  and  the  child  had  not  returned. 
Therefore  she  flew  out  of  the  open  window  and 
distended  herself  from  the  black  skin  of  a  native  who 
was  sleeping  in  the  backyard  ;  his  ankles  supplied 
her  wants  readily.  The  next  night  the  baby  in  the 
cot  satisfied  her  through  his  mosquito  net,  which  was 
badly  tucked  in  under  the  mattress  ;  and  again  she 
noticed  the  absence  of  her  brethren,  but  noted  that 
the  numbers  of  her  sisters  on  the  net  had  increased — 
somebody  had  opened  the  cesspool  and  they  had 
flown  out  in  search  of  blood.  Four  nights  later  she 
had  her  revenge  on  the  sleeper  in  the  front  room,  for 
he  was  tossing  about  in  the  semi-delirium  of  fever. 
She  gorged  herself,  and  was  satisfied  enough  to  sleep 
for  hours  after.  She  rested  every  day  and  fed  every 
night  until  she  had  made  the  acquaintance  of  every 
member  of  the  household,  including  all  the  servants. 
She  even  knew  the  geography  of  the  house  and  the 
taste  of  the  water  on  all  the  washhand-stands.  But 
for  the  occasional  bats,  lizards,  spiders,  and  a  bird  in 
the  garden,  her  life  was  a  peaceful  one.  However,  as 
she  grew  older  she  learned  to  avoid  such  enemies  by 
hiding,  and  she  knew  exactly  how  to  get  under  the 
bed  when  a  sleeper  woke  and  tried  to  squash  her 
distended  body. 

As  time  progressed  the  eggs  within  her  developed, 
and  she  felt  the  weight  of  pregnancy  bearing  upon 
her.  Her  meals  of  blood  had  been  regular  and  fre- 
quent, and  she  was  ready  to  lay  her  first  brood  within 


THE    MOSQUITO'S   TRAGEDY  93 

a  fortnight  of  her  first  meal  of  blood.  Where  should 
she  go  to  lay  her  eggs  ?  She  had  tried  all  the  water 
in  the  house,  but  it  was  all  clean  and  filtered  ;  it 
contained  no  food  for  her  young.  She  searched  the 
house.  If  she  did  lay  her  eggs  on  the  clean  water  in 
the  jug,  there  would  be  no  male  for  her  to  consort 
with  again.  She  looked  everywhere — no  males. 

At  last  she  determined  to  return  to  the  cesspool 
where  she  had  been  born.  She  knew  that  there 
would  be  males  of  her  species  therein,  and  that  the 
water  would  contain  plenty  of  food  for  her  young 
larvae  when  they  had  hatched  out  of  the  eggs.  She 
flew  down  the  stone  stairs,  through  the  chink  in  the 
wall  of  the  cellar  ;  but  a  new  smell  confronted  her — 
petroleum.  The  surface  of  the  water  was  covered 
with  it.  Everywhere  she  went  the  oil  faced  her. 
There  were  no  males  here.  No  mosquitos  of  any 
kind.  What  was  she  to  do  ?  She  could  not  lay  her 
eggs  on  oil.  So  she  left  her  birthplace  and  sought 
another  water  collection.  Everywhere  she  found 

«/ 

the  work  of  the  mosquito  brigade.  Utensils  were 
either  empty  or  contained  only  clean  water,  and  all 
stagnant  water  had  been  recently  oiled. 

Eventually,  after  searching  in  every  direction,  she 
wandered  to  another  house  and  found  a  fountain  in 
the  garden.  The  water  contained  many  mosquito 
larvae.  There  had  been  goldfish  there,  but  they  had 
died  for  some  unknown  reason,  and  the  mosquito 
brigade  had  not  noticed  the  fact.  She  laid  her  eggs 
on  the  still  water  during  the  night,  and  in  the  morning 
found  a  newly  hatched  male  to  fill  her  exhausted 


94  MOSQUITO    REDUCTION 

spermathecae  with  his  spermatozoa.  Then  she  re- 
entered  the  adjoining  house  and  started  feeding  again ; 
but  she  noticed  how  the  mosquitos  had  almost  disap- 
peared. This  was  of  some  advantage  to  her,  for  the 
inmates  of  the  house  no  longer  used  mosquito  cur- 
tains and  she  was  able  to  feed  uninterruptedly. 

Six  weeks  later  she  had  another  brood  of  eggs  to 
lay.  The  fountain  was  now  dry.  She  searched  high 
and  low,  but  there  was  no  water  anywhere  that  was 
suitable  for  her  eggs  ;  also  there  were  no  male  mos- 
quitos. All  the  cesspools  contained  petroleum,  and 
even  the  cisterns  were  screened  with  wire  gauze.  So 
she  laid  her  eggs  in  some  clean  water  in  a  basin,  but 
the  larvae  died  for  want  of  food.  She  searched 
for  a  male  mosquito  of  her  species  to  consort  with 
again  ;  he  could  not  be  found.  There  were  no  mos- 
quitos at  all.  Then  the  craving  for  blood  seemed  to 
forsake  her.  She  became  a  vegetarian,  living  on  the 
juices  of  old  banana  skins  and  discarded  water- 
melons. But  her  life,  once  so  full  of  adventure,  was 
blasted,  and  she  died  disappointed,  but  with  the 
knowledge  that  she  had  lived. 

Such  is  the  tragedy  of  the  last  of  the  mosquitos  ; 
it  is  the  only  tragedy  of  a  mosquito  campaign  if 
the  latter  is  properly  carried  out — the  remainder  is 
comedy,  and  an  interesting  one.  The  mosquitos 
disappear  rapidly.  In  a  few  weeks,  even  in  the  hot 
weather,  there  will  be  comparatively  few  insects  left. 
After  three  weeks,  at  Port  Said,  many  of  the  mos- 
quito nets  were  put  up  for  good.  In  parts  of  the 
town  where  leaky  cesspools  existed,  mosquitos  per- 


THE   MOSQUITOS    REDUCED  95 

sisted  or  returned  in  one  or  two  houses,  and  this 
happens  now  if  the  mosquito  brigade  stops  work 
for  a  single  week. 

The  male  mosquitos  are  the  first  to  be  reduced. 
Their  lives  are  so  short  that  if  their  birth-rate  is 
suddenly  curtailed  their  population  disappears  almost 
at  once.  Then  the  existing  females  cannot  effect  the 
coitus  necessary  after  laying  a  number  of  eggs.  They 
also  cease  to  annoy  human  beings.  Any  food  would 
seem  to  suit  these  widows  ;  they  are  not  very  par- 
ticular about  blood-sucking  when  they  have  no  eggs 
to  mature. 

So  mosquitos  ceased  to  trouble,  and  with  them 
went  the  fever.  The  unhealthy,  pallid-cheeked  chil- 
dren, the  unemployed  men,  and  the  sick  wife  disap- 
peared with  the  fever,  and  the  misery  became  ameli- 
orated. Away  went  most  of  the  professional  beggars, 
the  factories  began  work  again  in  the  summer,  and 
the  workshops  had  no  need  to  close.  The  attendance 
at  the  schools  is  now  good  and  the  children  are  well 
and  strong.  They  have  some  colour  in  their  cheeks, 
and  are  able  to  play  on  the  beach — it  is  a  very 
different  state  of  affairs.  The  place  is  buzzing,  docks 
are  being  constructed,  shipping  dues  are  rolling  in, 
and  trade  is  progressing.  It  has  cost  about  £1,000  a 
year,  or  sixpence  per  head  of  population  annually. 


CHAPTER    X 

REPORTING   PROGRESS 

WHILE  mosquito  reduction  is  in  progress  it  is  inter- 
esting to  watch  the  fever  reduction.  Unfortunately, 
there  is  no  exact  method  known  by  which  the  number 
of  mosquitos  in  a  locality  can  be  counted.  Many 
attempts  have  been  made  to  estimate  the  numbers 
of  mosquitos  in  a  town  ;  all  are  unsatisfactory.  The 
total  number  of  stagnant  water  collections  and  the 
percentage  of  those  infected  with  mosquito  larvae 
estimated  before  and  after  the  mosquito  campaign  is 
started  has  often  been  employed  as  a  method  of 
reporting  the  results  of  a  campaign  ;  but  the  method 
is  not  exact.  For  example,  when  the  first  estimate 
is  made,  a  house  may  be  declared  to  contain  no 
suitable  water  collections  and  to  be  free  from  mos- 
quito larvae.  Then  while  the  work  is  in  progress  a 
native  servant  may  leave  a  bucket  of  dirty  water 
hidden  in  a  corner  of  the  kitchen,  and  the  house  will 
become  full  of  mosquitos  (thousands  of  mosquitos 
may  be  produced  from  a  single  saucer  of  water  in 
three  weeks).  This  will  vitiate  the  results  at  once. 
There  is  no  accurate  means  of  counting  the  num- 
ber of  mosquitos  in  a  house,  or  even  in  a  room. 

96 


p.  96] 


A  favourite  breeding-place  for  domestic  mosquitos. 


COUNT   THE   MALE    MOSQUITOS  97 

Several  kinds  of  mosquito  traps  have  been  devised, 
but  they  give  little  exact  information.     For  every  ten 
mosquitos  caught  in  a  trap  there  are  probably  hun- 
dreds   that    avoid    capture.     The    writer    has    tried 
many  experiments  with  traps,  but  has  been  obliged 
to  give  them  up.     There  is  one  simple  way  by  which 
a    rough    estimate    of    mosquito    reduction    can    be 
obtained.     It  has  been  stated  before  that  the  first 
mosquitos  to  be  reduced  will  be  the  males.     Male 
mosquitos  habitually  remain  for  their  short  lives  near 
the  breeding-place  where  they  themselves  were  born. 
Only  occasionally  does  a  male  follow  the  females  into 
houses  ;   the  large  proportion  remain  near  the  water 
to  fertilise  the  females  as  they  emerge  from  the  pupa. 
But  in  a  room  infested   with  female  mosquitos  an 
occasional  male  will  find  his  way  there  to  fertilise  a 
possible  virgin  female  that  has  wandered  with  her 
sisters  into  the  house.     These  males  can  be  counted 
before  the  anti-mosquito  measures  start,  and  counted 
again    a    month    after.     Choose    several    houses    in 
scattered  parts  of  the  town,  and  in  one  of  the  bed- 
rooms of  each   count  the   number    of  males  found 
resting  on  the  mosquito  curtains.     Note  the  houses 
and  the  rooms,  and  utilise  them  again  for  the  next 
count.     If  there  is  a  reduction  of  males,  the  work  of 
mosquito  prevention  is  going  on  well.     Examine  the 
nets  in  the  morning.     If  after  some  weeks  there  are 
still  males  to  be  seen  on  the  nets,  it  is  certain  that 
there  are  yet  breeding-places  to  be  dealt  with.     If  on 
one   mosquito  curtain  there   are   several  male   mos- 
quitos, it  is  only  necessary  to  find  the  breeding-place 
7 


98  REPORTING   PROGRESS 

that  has  been  overlooked  by  the  brigade ;  it  is 
probably  on  the  premises.  This  method  is  only  a 
rough  one,  and  cannot  be  relied  on  to  give  exact 
information ;  several  males  may  be  found  in  one 
room,  and  not  one  in  another,  even  in  the  same 
house.  Domestic  mosquitos  do  not  fly  far  from  their 
breeding-places,  as  already  proved.  If,  however,  a 
mosquito  campaign  is  perseveringly  conducted,  the 
insects  will  be  reduced  so  rapidly  that  an  exact 
estimate  of  that  reduction  is  hardly  necessary. 

The  most  satisfactory  result  that  can  be  reported 
is  the  reduction  in  the  amount  of  fever.  The  fever 
census  should  be  taken  periodically.  Pay  a  visit  again 
to  all  the  schools.  Medical  examination  of  all  school- 
children is  now  a  recognised  routine  health  measure. 
Mosquito  reduction  is  an  excellent  excuse  for  its  in- 
stitution, if  such  be  needed.  Examine  a  hundred 
scholars  every  day.  Arrange  with  the  schoolmasters 
that  a  hundred  children  be  drawn  up  in  the  quad- 
rangle or  yard,  or  playground,  or  large  classroom, 
and  then  send  down  a  doctor,  or,  if  this  is  impossible, 
an  interested  school  visitor.  Inspect  the  children. 
How  many  out  of  the  hundred  have  anaemic,  pasty 
faces  ?  How  many  have  eye  disease  ?  How  many 
have  loathsome  skin  diseases  ?  How  many  have 
swollen  bellies  or  enlarged  spleens  ?  What  is  the 
total  number  of  scholars,  and  how  many  are  now 
absent  sick  ?  How  does  this  number  compare  with 
the  figures  obtained  at  the  first  fever  census  ?  If 
any  of  the  children  are  "  doubtfully  ill,"  place  them 
together  on  one  side,  and  examine  them  more  care- 


A  cesspool  under  a  native  hut  will  produce  many  mosquitos  and  much  sickness. 


Native  child  with  an  enormously  enlarged  spleen  from  malaria. 


p.  99] 


COUNT   THE    HEALTHY   CHILDREN  99 

fully,  making  them  lie  down  on  a  table  or  form.  Be 
gentle,  for  if  one  child  begins  to  cry  all  the  rest  will 
follow  suit  out  of  sympathy,  and  that  will  be  the  end 
of  the  examination — crying  is  a  catching  complaint. 
Try  to  find  out  what  is  the  matter  with  the  sick 
children.  Ask  them  whether  there  is  any  sickness  at 
home.  If  there  is  any  fever  amongst  the  school- 
children, ask  the  master  to  keep  a  register  of  those 
who  are  affected,  and  again  carefully  observe  the 
same  children  when  making  the  next  census.  If  this 
is  done  throughout  the  town  schools,  the  most  inter- 
esting facts  will  come  to  light.  But  examine  the 
healthy  as  well  as  the  sick. 

It  is  not  sufficient  to  inspect  the  European  school- 
children alone.  Go  into  the  native  locations  and  look 
at  the  children  there.  Perhaps  malarial  spleens  will 
be  found,  or  "  latent  "  yellow  fever.  Examine  the 
children  in  their  houses  or  in  the  streets,  and  keep  a 
record  of  them.  If  there  is  malaria,  a  hunt  for  the 
Anophelines  must  at  once  be  instituted ;  or  if  yellow 
fever  is  suspected,  it  must  be  dealt  with  at  once  by 
house  fumigation,  isolation  and  screening  of  the 
sick,  etc. 

This  is  the  most  interesting  and  gratifying  form 
of  •  public  health  administration  ;  and  all  the  time 
there  is  the  knowledge  that  progress  is  being  made. 
Inquiries  may  again  be  made  of  the  factories,  similar 
to  when  taking  the  first  fever  census.  Every  six 
months  the  examination  of  the  town  should  be  ac- 
complished, and  at  the  end  of  the  year  the  fever 
census  must  be  taken  in  precisely  the  same  way  as 


100  REPORTING   PROGRESS 

before,  and  the  results  compared.  But  there  must 
be  no  "  jumping  "  to  conclusions.  It  is  quite  insuffi- 
cient to  examine  a  hundred  schoolchildren  and  to  find 
only  two  of  them  absent  for  fever,  where  formerly 
five  were  laid  up,  and  then  to  conclude  that  there  is 
a  reduction  in  the  town  of  three  per  cent.  Such  a 
conclusion  is  quite  unjustified.  There  would  be  such 
a  statistical  error  that  the  conclusion  would  be  wrong. 
This  is  random  sampling,  and  it  gives  erroneous  im- 
pressions. Strictly  speaking,  all  the  schools  in  the 
town  should  be  examined  at  least  once  a  year,  and 
more  frequently  if  possible.  Omit  no  detail,  and  be 
careful  and  painstaking — it  will  be  well  rewarded. 

Collect  all  the  figures  available,  and  correlate 
them.  The  percentages  must  be  worked  out  from  the 
whole,  not  from  individual  units.  Remember  that 
"  averages  are  numerical  expressions  of  possibilities  ; 
extreme  values  are  expressions  of  probabilities." 
Also  that  "  the  value  of  a  series  of  observations  in- 
creases with  the  number  of  observations  ;  the  value 
of  the  deductions  with  the  square  root  of  that 
number."  How  frequently  official  reports  claim  the 
reduction  of  a  disease  in  a  large  community  because, 
out  of  a  hundred  in-patients  treated  in  one  hospital, 
ten  per  cent,  suffered  from  that  disease  compared  with 
fifteen  per  cent,  the  year  before  1  Such  an  inference 
is  not  only  unjustified,  but  is  actually  incorrect.  If 
deductions  are  drawn  from  percentages  or  averages, 
large  numbers  must  be  employed. 

An  interim  report  should  be  published.     It  should 
describe  the  area  dealt  with  by  the  mosquito  mea- 


DRAW   CONCLUSIONS   CAREFULLY          101 

sures,  the  difficulties  encountered,  the  personnel 
employed,  the  amount  of  oil  used,  and  it  should 
include  a  statement  of  accounts.  The  fever  census 
returns  should  be  quoted,  but  no  deductions  or  claims 
of  reduction  of  fever  incidence  should  be  made  in  six 
months,  for  example.  A  much  longer  time  must  be 
given  before  any  such  results  can  be  expected  in 
numerical  form  free  from  error,  although  the  fever 
has  been  reduced  without  doubt.  In  the  same  report 
some  of  the  more  sanitary  backslidings  of  the  town 
may  be  described,  and  their  remedies  suggested. 

In  this  report  an  important  point  may  be  em- 
phasised. Mosquitos  are  a  disgusting  household  pest. 
By  their  diminution  the  town  is  being  rid  of  a  plague. 
Any  one  who  has  visited  the  tropics  will  testify  to  the 
discomfort  caused  by  the  domestic  mosquito.  Even 
in  subtropical  countries  this  holds  good.  A  visit  to 
Venice,  for  example,  is  spoiled  by  the  misery  induced 
by  Culex  jatigans  and  Stegomyia  calopus.  In  the 
summer,  when  Venice  is  most  picturesque,  these  mos- 
quitos  make  life  unendurable  ;  the  former  annoys  at 
night,  the  latter  all  day  long.  The  hotels  are  full  of 
them,  and  these  species  attack  the  tourists  even  in 
gondolas  on  the  canals  ;  they  give  one  no  peace.  All 
day  long  one  is  squashing  the  striped  Stegomyiae,  and 
the  Culices  bite  one's  ankles  during  dinner  ;  the  mos- 
quito net  effectively  keeps  out  the  fresh  sea  breeze 
on  hot  evenings.  Venice  could  be  cleared  of  this  pest 
with  the  expenditure  of  some  energy  and  a  small 
sum.  The  cesspools  could  easily  be  dealt  with  as  at 
Port  Said  and  Ismailia.  Culex  and  Stegomyia  do  not 


102  REPORTING   PROGRESS 

breed  in  the  sea  water  of  the  Adriatic  ;  there  are  ho 
larvae  in  the  Grand  Canal.  It  is  only  a  matter  of 
simple  sanitation.  Venice  is  unhealthy  during  the 
summer  months  (if  not  all  the  year  round),  as  Port 
Said  was  ;  and  it  is  largely  due  to  mosquitos.  It  is 
such  a  pity. 

There,  whether  one  rests  in  the  hotel  lounge  or 
outside  a  cafe,  or  idles  away  an  hour  in  a  gondola 
exploring    the    water    byways,    one   is    incessantly 
scratching  and  grumbling,  or  striving  to  smite  these 
irritating  insects  which  have  just  risen  like  a  miasm 
from  a  Venetian   cesspool.     How  can  the  stones  of 
Venice  be  appreciated  under  such  conditions  ?     Then 
the  traveller  returns  disgusted  and  irritated  to  his  hot 
bedroom  at  the  hotel,  and  sits  by  the  open  window 
to  enjoy  the  breeze  and    the  oft-repeated,  twangy 
Neapolitan  serenade  that  is  being  "  breathed  "  be- 
neath him.     His  thoughts  fly  back  to  the  Doges,  and 
the  Rule  of  the  Ten  perhaps,  to  Byron,  or  to  Ruskin, 
only  to  be  suddenly  awakened  to  the  hard  and  matter- 
of-fact  present  by  the  bite  of  a  Culex  or  the  "  ping  "  of  a 
Stegomyia — the  flight  of  the  mosquito  is  quicker  than 
his  thought.     At  last  the  traveller  is  driven  to  bed, 
pursued  by  this  persistent  pest,   and  he  lies  there 
panting,  sweating,  and   cursing  under  the  mosquito 
net.     Then  does  his  sympathy  go  out  to  those  Ancient 
Venetians  who  forsook  their  home  to  settle  elsewhere 
in  the  Mediterranean  and  the  Levant,  where  they 
built  picturesque  old  cities  on  high  walls  that  were 
surrounded  by  sea. 

Natives  and  persons  long  resident  in  the  tropics 


MISERY   AND   DISCOMFORT   REMEDIED       103 

sometimes  become  so  accustomed  to  inoculation 
with  mosquito  saliva  that  it  fails  to  irritate  them. 
They  frequently  aver  that  they  are  not  bitten.  But 
examine  their  mosquito  nets  in  the  morning ;  there 
will  be  plenty  of  recently  fed  females  there.  The  old 
residents  become  immune  to  mosquito  poison.  Ex- 
amine the  arms  and  face  of  a  newly  born  infant  in  a 
house  that  is  mosquito-infested  and  look  at  the  wheals 
produced  by  the  insects  ;  no  wonder  the  child  cries 
at  night. 

Mosquito  reduction  will  relieve  all  this  misery, 
and  it  will  do  so  very  quickly.  Here  alone  is  sufficient 
excuse  for  its  institution  and  maintenance,  even  if  it 
is  certain  that  there  is  no  fever. 


CHAPTER    XI 

FINANCE 

THE  municipal  cashier  should  be  directed  to  keep  the 
accounts   of  the  mosquito  credit  or  fund  under  a 
separate  entry  ;    otherwise  all  sorts  of  undertakings, 
charitable  and  otherwise,  will  cause  leakage  of  the 
money.     Nothing   should   be   paid   from   the   credit 
unless  formally  approved  by  the  person  who  is  direct- 
ing the  work.     There  must  be  a  responsible  head,  or 
the  funds  will  be  diverted  to  other  uses.     As  stated 
before,  the  local  health  officer  is  the  best  organiser  for 
a  mosquito  campaign,  but  this  is  not  absolutely  neces- 
sary.    Whoever    directs    operations    must    see    that 
there  is  no  "  juggling  "  with  the  collected,  subscribed, 
or  granted  funds.     After  the  campaign  has  started, 
if  the  necessity  for  major  sanitary  works  becomes 
apparent,  and  these  are  agreed  upon,  credits  allowed 
for  them  should  be  kept  separate.     Then  should  any 
one  of  them  fail,  its  downfall  will  not  include  the 
measures  against  mosquitos.     Payment  of  bills,  etc., 
and  the  salaries  must  be  made  regularly.     Proper 
pay-sheets  for  the  foremen  and  workmen  should  be 
employed,  so  that  records  of  promotions,  rates  of  pay, 
punishments,  etc.,  may  be  kept. 

104 


HEALTH    AND    CREDIT  105 

Perhaps  during  the  early  part  of  the  campaign 
some  displeased  landlord,  who  has  been  forced  to  put 
his  house  in  order,  may  cavil  at  the  expenditure, 
hoping  to  undermine  the  cause.  It  is  best  to  ignore 
such  busybodies  ;  but  if  he  is  powerful,  and  an  answer 
is  pressed  for,  it  is  ready  to  hand.  The  question  of 
public  health  is  one  of  finance.  What  is  the  value  of 
a  human  life  to  the  community  ?  Thirty  years  ago, 
in  the  old  slave  market  at  Zanzibar,  it  was  possible 
to  buy  a  negro  woman-slave  for  twenty  pounds.  Her 
purchase,  from  capital,  would  save  her  master  from 
paying  her  regular  wages  of  about  £l  per  month,  but 
her  food  cost  him  something.  In  Egypt  to-day  a 
native  labourer  can  command  £2  per  month,  or  £24 
per  year.  Every  one  of  these  labourers  contributes 
towards  the  welfare  of  the  State  by  paying  taxes, 
either  direct  or  indirect,  by  working  so  that  the  taxed 
imports  and  exports  are  swelled,  and  by  contributing 
to  the  progress  of  the  communities  of  the  towns  and 
villages.  It  is  by  the  size  and  industries  of  these 
towns  that  the  stability  and  progress  of  the  State  are 
judged.  The  credit  which  a  State  can  command 
varies  directly  with  the  amount  of  work  done  in  it ; 
that  is,  it  is  dependent  on  its  industrial  output.  But 
this  industrial  output  varies  with  the  number  of 
inhabitants,  and  their  ability  to  work ;  and  their 
numbers  and  ability  to  work  vary  directly  with  their 
health.  This  is  a  platitude  of  political  economy,  but 
it  is  one  that  appears  to  be  seldom  realised.  The 
question  therefore  is  answered  :  The  value  of  a 
human  life  varies  directly  with  health ;  the  same  may 


106  FINANCE 

be  said  of  the  community.  England  is  the  healthiest 
nation  in  the  world  and  it  is  the  richest.  At  Zanzibar, 
the  cost  of  the  least  valuable  of  human  lives  used  to 
be  £20.  But  suppose  the  slave  died,  then  the  capital 
expended  upon  her  was  lost  (for  there  was  no  insur- 
ance company  to  insure  slaves  at  Zanzibar  in  those 
days),  as  was  the  work  that  would  have  been  done  by 
her.  Or  if  she  was  constantly  ill  and  unable  to  work, 
the  cost  to  her  master  was  even  greater,  for  she  had 
to  be  provided  for  during  her  illness  ;  it  was  increas- 
ing capital  expenditure  with  compound  interest. 
But  if  the  slave's  life  could  have  been  saved,  or  her 
illness  avoided,  then  the  capital  expended  on  her 
would  have  been  actually  repaid  by  her  work.  All 
persons  are  slaves  of  the  State  in  which  they  live, 
and  for  which  they  work,  and  if  they  are  healthy 
they  will  gradually  repay  any  capital  that  is  expended 
by  it  on  their  welfare. 

If  the  State  pays  sixpence  per  head  of  popula- 
tion per  year,  and  thus  renders  the  whole  community 
free  from  certain  diseases,  or  if  it  merely  renders  the 
life  of  that  community  more  comfortable,  the  capital 
sunk  to  produce  the  sixpences  (£33,000  at  3  per  cent, 
for  a  community  of  50,000)  will  soon  be  repaid.  The 
death-rate  will  fall,  and  healthy  children  will  grow  up 
instead  of  unhealthy  ones.  Every  healthy  child  is 
an  actual  financial  asset  to  the  State,  for  it  will  do 
its  share  in  increasing  the  industrial  output.  And 
this  increasing  output  will  improve  the  credit  of  the 
State.  As  the  success  of  the  mosquito  campaign 
becomes  established,  and  the  insects  disappear,  the 


HEALTH    IS   CREDIT  107 

cost  of  the  upkeep  of  the  work  will  diminish.  But 
in  the  meantime  the  town  will  progress,  its  financial 
position  will  improve,  for  its  credit  will  become 
cheaper  and  greater.  Ultimately  its  population  will 
increase  because  a  falling  death-rate,  progress,  and 
the  improving  credit  will  attract  immigration,  and 
then  the  rate  of  sixpence  per  head  per  year  will  fall 
until  perhaps  a  penny  will  be  sufficient.  At  Port 
Said  during  the  first  year  of  the  mosquito  campaign 
41,120  gallons  of  petroleum  were  used,  but  during  the 
second  year  only  31,670  gallons  were  required.  In 
that  town,  also,  the  campaign  cost  £1,176  the  first 
year  (1907),  and  this  sum  fell  to  £1,023  in  the  second 
year.  Now  (1910)  the  annual  cost  is  only  £800,  and 
the  population  of  the  town  is  increasing  rapidly. 
Lastly,  the  improving  credit  of  the  place  must  have 
repaid  the  capital  buried  more  than  once  already. 
Other  towns,  Ismailia,  Havana,  Rio,  New  Orleans, 
Klang,  Santos,  Colon,  Panama,  etc.,  tell  the  same 
story.  So  if  the  work  has  been  well  performed,  and 
successfully  carried  out  and  maintained,  the  pro- 
fessional grumbler  will  soon  be  gagged  by  the  weight 
of  public  opinion. 

It  is  as  well,  however,  to  curtail,  as  far  as  possible, 
all  unnecessary  expenditure.  See  that  the  workmen 
do  not  waste  oil.  One  lazy  man  may  pour  all  his 
allowance  of  oil  into  one  cesspool,  and  then  rest  in 
a  cafe  for  the  remainder  of  the  day.  If  he  does  this, 
the  mosquitos  will  reappear  in  the  neglected  houses, 
and  complaints  will  soon  come  in.  As  his  name  is 
written  on  the  door  of  these  houses,  he  will  soon  be 


108  FINANCE 

discovered  and  can  be  punished.  At  the  end  of  every 
year  the  amount  of  oil  may  again  be  put  out  to  tender 
and  the  cheapest  offer  accepted  ;  perhaps  an  economy 
may  be  effected  in  this  way.  So  much  oil  may  not 
be  required  as  before  ;  the  exact  amount  required 
can  be  estimated  from  the  foremen's  notebooks. 
After  a  time,  when  the  mosquitos  have  almost  com- 
pletely disappeared,  the  staff  employed  may  be  cur- 
tailed ;  but  this  should  be  done  cautiously.  By  a 
little  foresight  and  thought,  the  area  of  water  surface 
to  be  dealt  with  every  week  may  be  reduced.  At 
Port  Said,  when  we  started,  we  found  400  cellars  in 
the  town  flooded  with  sewage  from  leaking  cesspools. 
These  cellars  were  underground  catacombs  of  sewage, 
having  7,296  square  metres  of  water  surface  to  be 
dealt  with  every  week.  They  were  therefore  filled  up 
with  sand  from  the  seashore.  It  was  done  by  the 
landlords  as  described  in  a  former  chapter.  Occa- 
sionally assistance  was  given  by  grants  from  the 
mosquito  fund,  for  it  was  realised  that  a  dry  cellar 
is  cheaper  than  constant  oiling. 

Then  again,  in  rainy  climates,  domestic  mosquitos 
will  sometimes  breed  in  holes  in  trees,  or  in  puddles 
in  walls,  or  in  backyards.  Detail  one  workman,  and 
give  him  some  cement  and  a  trowel,  and  he  will  pro- 
duce an  economy  of  several  pounds  in  the  annual  oil- 
bill.  The  foreman  must  be  charged  not  to  leave  a 
full  oil-cart  in  the  hot  sun  or  it  will  become  leaky, 
or  even  burst,  and  the  oil  will  be  wasted.  Much 
money  may  be  saved  by  attending  to  small  items  of 
this  nature.  In  large  open  water  collections  oil  may 


ECONOMY  109 

be  economised  by  stocking  them  with  fish  or  with 
the  water-beetle  Notonecta,  "  the  water-boatman." 
Even  when  these  exposed  pools  are  oiled  the  wind 
may  bank  it  up,  and  then  the  mosquito  larvae  will 
thrive.  Advise  the  municipality  to  fill  up  such  places 
or  to  turn  them  into  ornamental  ponds,  and  put  in 
some  goldfish.  But  in  this  case  see  that  the  fish  do 
not  die  ;  examine  them  periodically.  Make  a  fore- 
man responsible  for  this. 

After  the  mosquitos  have  been  reduced  and  the 
work  is  well  maintained,  it  will  become  apparent  that 
much  labour  would  be  saved  if  the  cesspools  were 
filled  up  and  replaced  by  an  efficient  system  of 
sewerage  by  water  carriage  ;  also  that  a  great  eco- 
nomy in  water  consumption  would  be  effected,  and 
water-tubs  and  cisterns  dispensed  with  by  a  good 
filtered-water  supply,  if  the  pressure  in  the  pipes  could 
be  made  sufficient  to  reach  the  top  stories  of  the 
highest  houses  in  the  town.  If  these  could  be  Installed, 
the  cost  of  the  mosquito  campaign  will  fall  consider- 
ably. But  it  is  quite  unreasonable  to  delay  the 
institution  of  anti-mosquito  measures  until  such 
major  sanitary  works  have  been  installed,  for  the 
fever  will  continue. 

In  one  or  two  towns  mosquito  measures  have  been 
said  to  have  failed  ;  for  example,  at  Mian  Mir,  in  India. 
This  is  because  it  was  not  properly  or  sincerely  car- 
ried out.  If  the  work  is  perseveringly  done,  it  is 
bound  to  succeed. 


CHAPTER    XII 

RESULTS 

AT  the  end  of  every  year  a  full  report  may  be  pub- 
lished giving  the  results  of  the  campaign  and  justify- 
ing the  expenditure  incurred.  If  the  notebooks  of 
the  foremen  or  moustiquiers  are  examined,  the 
number  of  water  collections  that  harbour  mosquito 
larvae  may  be  enumerated  and  compared  with  that 
obtained  when  the  original  estimate  was  made.  The 
difference  can  be  recorded.  Then  the  fever  census 
will  give  interesting  results  ;  but  caution  must  be 
exercised,  as  already  stated,  in  drawing  conclusions. 
Usually  some  years  must  elapse  before  such  deduct- 
tions  are  justified,  although  there  is  a  marked  re- 
duction of  the  numbers  of  insects  and  the  town  is 
obviously  healthier.  Every  effort  must  be  made  to 
obtain  exact  information.  Regardless  of  the  truth, 
natives  have  a  happy  way  of  expressing  opinions 
that  they  think  will  please  the  questioner,  and  this 
fact  must  be  remembered.  Others  also  will  some- 
times cover  the  truth  with  a  veneer  of  exaggeration 
if  they  think  they  will  go  up  in  the  estimation  of  the 
Health  Department  or  municipal  councillor — it  may 

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ADVERTISE    RESULTS  111 

assist  them  sometime  if  they  are  "  diplomatic." 
Care  must  always  be  exercised  in  accepting  very 
favourable  reports  from  such  persons. 

An  attempt  should  be  made  at  the  end  of  each 
year  to  classify  the  fevers  affecting  the  town.  The 
doctors'  returns  should  help  in  this.  In  most  tropical 
towns  there  are  many  different  kinds  of  fever  which 
are  most  confusing.  There  are  typhoid,  Malta  fever, 
malaria,  simple  continued  fever,  dengue,  twelve-day 
fever,  seven-day  fever,  and  the  phlebotomus,  or  three- 
day  fever,  recently  differentiated.  Then  there  is  the 
possibility  of  latent  yellow  fever,  the  fever  accom- 
panying ankylostomiasis,  endemic  cirrhosis  of  the 
liver,  sleeping  sickness,  kala  azar,  and  a  host  of  other 
affections  as  well  as  the  zymotic  diseases.  It  is  not 
always  easy  to  differentiate  between  these,  and  some- 
times it  is  impossible. 

It  will  require  a  great  deal  of  painstaking  research 
before  all  these  diseases  can  be  diagnosed  from  each 
other  with  certitude.  But  in  the  meantime  efforts 
may  be  made  to  collect  information  from  all  sources 
about  them.  One  good  source  is  a  carefully  con- 
ducted mosquito  campaign.  The  figures  obtained 
from  a  frequent  fever  census  taken  before,  during, 
and  after  the  mosquito  reduction  will  certainly  be  of 
the  utmost  use  when  attention  is  drawn  to  the 
anomalous  fevers  of  warm  climates,  and  researches 
upon  them  begun  seriously.  If  fever  statistics  are 
drawn  up  carelessly,  however,  they  will  be  useless  for 
such  a  purpose. 

The  results  should  be  published  broadcast.     The 


112  RESULTS 

cause — mosquito  reduction — is  only  in  its  infancy,  and 
it  is  important  that  it  should  be  instituted  everywhere 
practicable.  This  can  only  be  brought  about  by 
placing  before  the  notice  of  the  public  its  possibilities 
and  the  methods  to  be  employed.  This  is  the  age  of 
advertisement,  and  advertisement  has  become  neces- 
sary if  any  new  project  is  to  succeed,  or  become 
generally  known.  Advertisement  for  such  a  cause  is 
surely  justifiable.  Publish  frequently,  but  let  the 
publication  be  accurate — then  others  can  learn  from 
the  experience  gained. 

It  may  be  finally  repeated  that  this  work  can  be 
carried  out  not  only  by  doctors  alone,  but  by  all 
persons  who  have  the  welfare  of  the  community  at 
heart.  A  scientific  training  is  not  absolutely  essen- 
tial for  the  accomplishment  of  mosquito  reduction. 
Local  Health  Departments  are  the  best  organisers  for 
anti-mosquito  measures,  but  any  really  interested 
and  responsible  person  in  a  town  or  village  can  do  it 
if  the  lines  laid  down  here  are  followed. 

Lastly,  it  must  be  clearly  understood  that  it  is 
not  possible  to  exterminate  mosquitos  in  a  given  town, 
or  even  part  of  a  town  ;  it  is  only  possible  to  reduce 
the  numbers  of  gnats.  Mosquitos  are  very  local  in 
their  habits  and  do  not  fly  far,  as  already  emphasised 
— the  fact  is  a  most  important  one.  At  Port  Said 
one  part  of  the  town  was  cleared  first,  while  another 
remained  untouched.  The  mosquito  nets  were 
largely  dispensed  with  in  the  cleared  district,  but  the 
insects  continued  as  numerous  as  ever  in  the  uncleared 
quarter  ;  only  one  street  separated  the  two  portions. 


PERSEVERE  113 

The  same  thing  occurred  in  Cairo.  Mosquito  migra- 
tion will  not  affect  in  any  way  the  work  of  clearing 
towns,  villages,  or  even  parts  of  towns,  of  the  insects. 
But  if  once  cleared,  and  the  work  is  allowed  to  fail  for 
any  reason,  the  mosquitos  will  surely  return.  At 
Ismailia  and  at  Port  Said,  if  the  mosquito  brigades 
stop  work  for  a  single  week — even  now  after  several 
years  of  continuous  work — mosquitos  return.  This 
shows  that  it  is  not  possible  to  exterminate  mosqui- 
tos ;  they  can  only  be  reduced.  But  this  reduction 
can  be  made  so  efficacious  that  the  insects  become 
reduced  to  a  negligible  quantity,  and  the  fevers  will 
be  exterminated.  Therefore  it  is  clearly  the  duty 
of  every  one,  wherever  mosquitos  exist,  to  start  pre- 
ventive measures  against  them,  including  those 
of  the  domestic  species,  in  that  extent  of  district  as 
means  will  allow.  Sooner  or  later  the  presence  of 
mosquitos  will  mean  the  presence  of  disease  carried  by 
them,  even  if  these  do  not  exist  already. 

After  the  mosquitos  have  been  reduced  to  negli- 
gible numbers,  and  the  work  is  being  well  maintained 
at  a  diminished  cost,  the  moustiquiers  may  be  em- 
ployed as  ordinary  sanitary  inspectors.  They  will  be 
well  acquainted  with  the  town,  with  all  its  houses, 
will  know  the  inhabitants,  who  in  turn  will  know 
them.  They  can  then  be  utilised  to  report  on  in- 
sanitary places,  unhealthy  shops  and  overcrowded 
factories,  dangerous  trades,  and  can  even  notify 
disease  or  cases  of  sickness.  They  will  learn  from  the 
servants  which  houses  have  sick  tenants,  and  such 
cases  can  be  investigated  early  and  dealt  with 
8 


114  RESULTS 

according  to  existing  customs.  After  mosquito  pre- 
vention has  become  an  accomplished  fact,  a  campaign 
against  flies  may  be  started  in  the  same  quarters. 
Flies  breed  in  manure  heaps,  stables,  cowsheds,  im- 
properly cleaned  streets,  ashbins,  slaughter-houses, 
refuse  depots,  etc.  The  moustiquiers  can  be  taught 
to  deal  with  such  places  as  part  of  their  routine  work. 
Fly  reduction  is  almost  as  important  as  mosquito 
reduction.  But  the  original  object  of  the  existence 
of  the  mosquito  brigades  should  never  be  lost  sight 
of.  Should  the  unpopular  mosquitos  return,  because 
the  moustiquiers  are  being  employed  for  other  duties, 
their  work  will  fall  into  disrepute,  and  they  will 
become  disheartened  by  complaints  and  grumblings. 
A  mosquito  campaign  once  started  must  always  be 
continued  with  undiminished  vigour. 


Printtdby  Batell,  Watson  &  Viney,  Ld.,  lanfan  and  Ayletbury. 


14  DAY  USE 

RETURN  TO  DESK  FROM  WHICH  BORROWED 

Ol 


This  book  is  due  on  the  last  date  stamped  below,  or 

on  the  date  to  which  renewed. 
Renewed  books  are  subject  to  immediate  recall. 


LD  21-50m-4,'63 


